mariadb/innobase/row/row0mysql.c

/******************************************************
Interface between Innobase row operations and MySQL.
Contains also create table and other data dictionary operations.

(c) 2000 Innobase Oy

Created 9/17/2000 Heikki Tuuri
*******************************************************/

#include "row0mysql.h"

#ifdef UNIV_NONINL
#include "row0mysql.ic"
#endif

#include "row0ins.h"
#include "row0sel.h"
#include "row0upd.h"
#include "row0row.h"
#include "que0que.h"
#include "pars0pars.h"
#include "dict0dict.h"
#include "dict0crea.h"
#include "dict0load.h"
#include "trx0roll.h"
#include "trx0purge.h"
#include "lock0lock.h"
#include "rem0cmp.h"
#include "log0log.h"
#include "btr0sea.h"

/* A dummy variable used to fool the compiler */
ibool	row_mysql_identically_false	= FALSE;

/* List of tables we should drop in background. ALTER TABLE in MySQL requires
that the table handler can drop the table in background when there are no
queries to it any more. Protected by the kernel mutex. */
typedef struct row_mysql_drop_struct	row_mysql_drop_t;
struct row_mysql_drop_struct{
	char*				table_name;
	UT_LIST_NODE_T(row_mysql_drop_t) row_mysql_drop_list;
};

UT_LIST_BASE_NODE_T(row_mysql_drop_t)	row_mysql_drop_list;
ibool	row_mysql_drop_list_inited 	= FALSE;

/* Magic table names for invoking various monitor threads */
static const char S_innodb_monitor[] = "innodb_monitor";
static const char S_innodb_lock_monitor[] = "innodb_lock_monitor";
static const char S_innodb_tablespace_monitor[] = "innodb_tablespace_monitor";
static const char S_innodb_table_monitor[] = "innodb_table_monitor";
static const char S_innodb_mem_validate[] = "innodb_mem_validate";

/* Name suffix for recovered orphaned temporary tables */
static const char S_recover_innodb_tmp_table[] = "_recover_innodb_tmp_table";
/***********************************************************************
Determine if the given name ends in the suffix reserved for recovered
orphaned temporary tables. */
static
ibool
row_mysql_is_recovered_tmp_table(
/*=============================*/
				 /* out: TRUE if table name ends in
				 the reserved suffix */
	const char*	name)
{
	ulint	namelen	= strlen(name) + 1;
	return(namelen >= sizeof S_recover_innodb_tmp_table
		&& !memcmp(name + namelen -
			sizeof S_recover_innodb_tmp_table,
			S_recover_innodb_tmp_table,
			sizeof S_recover_innodb_tmp_table));
}

/***********************************************************************
Determine if the given name is a name reserved for MySQL system tables. */
static
ibool
row_mysql_is_system_table(
/*======================*/
				 /* out: TRUE if name is a MySQL
				 system table name */
	const char*	name)
{
	if (memcmp(name, "mysql/", 6)) {
		return(FALSE);
	}
	return(0 == strcmp(name + 6, "host")
	    || 0 == strcmp(name + 6, "user")
	    || 0 == strcmp(name + 6, "db"));
}
/***********************************************************************
Reads a MySQL format variable-length field (like VARCHAR) length and
returns pointer to the field data. */

byte*
row_mysql_read_var_ref_noninline(
/*=============================*/
			/* out: field + 2 */
	ulint*	len,	/* out: variable-length field length */
	byte*	field)	/* in: field */
{
	return(row_mysql_read_var_ref(len, field));
}

/***********************************************************************
Stores a reference to a BLOB in the MySQL format. */

void
row_mysql_store_blob_ref(
/*=====================*/
	byte*	dest,		/* in: where to store */
	ulint	col_len,	/* in: dest buffer size: determines into
				how many bytes the BLOB length is stored,
				the space for the length may vary from 1
				to 4 bytes */
	byte*	data,		/* in: BLOB data; if the value to store
				is SQL NULL this should be NULL pointer */
	ulint	len)		/* in: BLOB length; if the value to store
				is SQL NULL this should be 0; remember
				also to set the NULL bit in the MySQL record
				header! */
{
	/* MySQL might assume the field is set to zero except the length and
	the pointer fields */

	memset(dest, '\0', col_len);

	/* In dest there are 1 - 4 bytes reserved for the BLOB length,
	and after that 8 bytes reserved for the pointer to the data.
	In 32-bit architectures we only use the first 4 bytes of the pointer
	slot. */

	ut_a(col_len - 8 > 1 || len < 256);
	ut_a(col_len - 8 > 2 || len < 256 * 256);
	ut_a(col_len - 8 > 3 || len < 256 * 256 * 256);

	mach_write_to_n_little_endian(dest, col_len - 8, len);

	ut_memcpy(dest + col_len - 8, (byte*)&data, sizeof(byte*));	
}

/***********************************************************************
Reads a reference to a BLOB in the MySQL format. */

byte*
row_mysql_read_blob_ref(
/*====================*/
				/* out: pointer to BLOB data */
	ulint*	len,		/* out: BLOB length */
	byte*	ref,		/* in: BLOB reference in the MySQL format */
	ulint	col_len)	/* in: BLOB reference length (not BLOB
				length) */
{
	byte*	data;

	*len = mach_read_from_n_little_endian(ref, col_len - 8);

	ut_memcpy((byte*)&data, ref + col_len - 8, sizeof(byte*));

	return(data);
}

/******************************************************************
Convert a row in the MySQL format to a row in the Innobase format. */
static
void
row_mysql_convert_row_to_innobase(
/*==============================*/
	dtuple_t*	row,		/* in/out: Innobase row where the
					field type information is already
					copied there, or will be copied
					later */
	row_prebuilt_t*	prebuilt,	/* in: prebuilt struct where template
					must be of type ROW_MYSQL_WHOLE_ROW */
	byte*		mysql_rec)	/* in: row in the MySQL format;
					NOTE: do not discard as long as
					row is used, as row may contain
					pointers to this record! */
{
	mysql_row_templ_t*	templ;	
	dfield_t*		dfield;
	ulint			i;
	
	ut_ad(prebuilt->template_type == ROW_MYSQL_WHOLE_ROW);
	ut_ad(prebuilt->mysql_template);

	for (i = 0; i < prebuilt->n_template; i++) {

		templ = prebuilt->mysql_template + i;
		dfield = dtuple_get_nth_field(row, i);

		if (templ->mysql_null_bit_mask != 0) {
			/* Column may be SQL NULL */

			if (mysql_rec[templ->mysql_null_byte_offset] &
 					(byte) (templ->mysql_null_bit_mask)) {

				/* It is SQL NULL */

				dfield_set_data(dfield, NULL, UNIV_SQL_NULL);

				goto next_column;
			}
		}			
		
		row_mysql_store_col_in_innobase_format(dfield,
					prebuilt->ins_upd_rec_buff
						+ templ->mysql_col_offset,
					mysql_rec + templ->mysql_col_offset,
					templ->mysql_col_len,
					templ->type, templ->is_unsigned);
next_column:
		;
	} 
}

/********************************************************************
Handles user errors and lock waits detected by the database engine. */

ibool
row_mysql_handle_errors(
/*====================*/
				/* out: TRUE if it was a lock wait and
				we should continue running the query thread */
	ulint*		new_err,/* out: possible new error encountered in
				lock wait, or if no new error, the value
				of trx->error_state at the entry of this
				function */
	trx_t*		trx,	/* in: transaction */
	que_thr_t*	thr,	/* in: query thread */
	trx_savept_t*	savept)	/* in: savepoint or NULL */
{
	ulint	err;

handle_new_error:
	err = trx->error_state;
	
	ut_a(err != DB_SUCCESS);
	
	trx->error_state = DB_SUCCESS;

	if (err == DB_DUPLICATE_KEY) {
           	if (savept) {
			/* Roll back the latest, possibly incomplete
			insertion or update */

			trx_general_rollback_for_mysql(trx, TRUE, savept);
		}
	} else if (err == DB_TOO_BIG_RECORD) {
           	if (savept) {
			/* Roll back the latest, possibly incomplete
			insertion or update */

			trx_general_rollback_for_mysql(trx, TRUE, savept);
		}
		/* MySQL will roll back the latest SQL statement */
	} else if (err == DB_ROW_IS_REFERENCED
		   || err == DB_NO_REFERENCED_ROW
		   || err == DB_CANNOT_ADD_CONSTRAINT) {
           	if (savept) {
			/* Roll back the latest, possibly incomplete
			insertion or update */

			trx_general_rollback_for_mysql(trx, TRUE, savept);
		}
		/* MySQL will roll back the latest SQL statement */
	} else if (err == DB_LOCK_WAIT) {

		srv_suspend_mysql_thread(thr);

		if (trx->error_state != DB_SUCCESS) {
			que_thr_stop_for_mysql(thr);

			goto handle_new_error;
		}

		*new_err = err;

		return(TRUE);

	} else if (err == DB_DEADLOCK || err == DB_LOCK_WAIT_TIMEOUT) {
		/* Roll back the whole transaction; this resolution was added
		to version 3.23.43 */

		trx_general_rollback_for_mysql(trx, FALSE, NULL);
				
	} else if (err == DB_OUT_OF_FILE_SPACE) {
           	if (savept) {
			/* Roll back the latest, possibly incomplete
			insertion or update */

			trx_general_rollback_for_mysql(trx, TRUE, savept);
		}
		/* MySQL will roll back the latest SQL statement */

	} else if (err == DB_MUST_GET_MORE_FILE_SPACE) {

		fputs(
		"InnoDB: The database cannot continue operation because of\n"
		"InnoDB: lack of space. You must add a new data file to\n"
		"InnoDB: my.cnf and restart the database.\n", stderr);
		
		exit(1);
	} else if (err == DB_CORRUPTION) {

		fputs(
	    "InnoDB: We detected index corruption in an InnoDB type table.\n"
	    "InnoDB: You have to dump + drop + reimport the table or, in\n"
	    "InnoDB: a case of widespread corruption, dump all InnoDB\n"
	    "InnoDB: tables and recreate the whole InnoDB tablespace.\n"
	    "InnoDB: If the mysqld server crashes after the startup or when\n"
	    "InnoDB: you dump the tables, look at section 6.1 of\n"
	    "InnoDB: http://www.innodb.com/ibman.php for help.\n", stderr);

	} else {
		fprintf(stderr, "InnoDB: unknown error code %lu\n", err);
		ut_error;
	}		

	if (trx->error_state != DB_SUCCESS) {
		*new_err = trx->error_state;
	} else {
		*new_err = err;
	}
	
	trx->error_state = DB_SUCCESS;

	return(FALSE);
}

/************************************************************************
Create a prebuilt struct for a MySQL table handle. */

row_prebuilt_t*
row_create_prebuilt(
/*================*/
				/* out, own: a prebuilt struct */
	dict_table_t*	table)	/* in: Innobase table handle */
{
	row_prebuilt_t*	prebuilt;
	mem_heap_t*	heap;
	dict_index_t*	clust_index;
	dtuple_t*	ref;
	ulint		ref_len;
	ulint		i;
	
	heap = mem_heap_create(128);

	prebuilt = mem_heap_alloc(heap, sizeof(row_prebuilt_t));

	prebuilt->magic_n = ROW_PREBUILT_ALLOCATED;
	prebuilt->magic_n2 = ROW_PREBUILT_ALLOCATED;

	prebuilt->table = table;

	prebuilt->trx = NULL;

	prebuilt->sql_stat_start = TRUE;

	prebuilt->mysql_has_locked = FALSE;

	prebuilt->index = NULL;

	prebuilt->used_in_HANDLER = FALSE;

	prebuilt->n_template = 0;
	prebuilt->mysql_template = NULL;

	prebuilt->heap = heap;
	prebuilt->ins_node = NULL;

	prebuilt->ins_upd_rec_buff = NULL;
	
	prebuilt->upd_node = NULL;
	prebuilt->ins_graph = NULL;
	prebuilt->upd_graph = NULL;

  	prebuilt->pcur = btr_pcur_create_for_mysql();
  	prebuilt->clust_pcur = btr_pcur_create_for_mysql();

	prebuilt->select_lock_type = LOCK_NONE;

	prebuilt->sel_graph = NULL;

	prebuilt->search_tuple = dtuple_create(heap,
						dict_table_get_n_cols(table));
	
	clust_index = dict_table_get_first_index(table);

	ref_len = dict_index_get_n_unique(clust_index);

	ref = dtuple_create(heap, ref_len);

	dict_index_copy_types(ref, clust_index, ref_len);

	prebuilt->clust_ref = ref;

	for (i = 0; i < MYSQL_FETCH_CACHE_SIZE; i++) {
		prebuilt->fetch_cache[i] = NULL;
	}

	prebuilt->n_fetch_cached = 0;

	prebuilt->blob_heap = NULL;

	prebuilt->old_vers_heap = NULL;

	return(prebuilt);
}

/************************************************************************
Free a prebuilt struct for a MySQL table handle. */

void
row_prebuilt_free(
/*==============*/
	row_prebuilt_t*	prebuilt)	/* in, own: prebuilt struct */
{
	ulint	i;

	if (prebuilt->magic_n != ROW_PREBUILT_ALLOCATED
	    || prebuilt->magic_n2 != ROW_PREBUILT_ALLOCATED) {
		fprintf(stderr,
"InnoDB: Error: trying to free a corrupt\n"
"InnoDB: table handle. Magic n %lu, magic n2 %lu, table name ",
		prebuilt->magic_n, prebuilt->magic_n2);
		ut_print_name(stderr, prebuilt->table->name);
		putc('\n', stderr);

		mem_analyze_corruption((byte*)prebuilt);

		ut_error;
	}

	prebuilt->magic_n = ROW_PREBUILT_FREED;
	prebuilt->magic_n2 = ROW_PREBUILT_FREED;

	btr_pcur_free_for_mysql(prebuilt->pcur);
	btr_pcur_free_for_mysql(prebuilt->clust_pcur);

	if (prebuilt->mysql_template) {
		mem_free(prebuilt->mysql_template);
	}

	if (prebuilt->ins_graph) {
		que_graph_free_recursive(prebuilt->ins_graph);
	}

	if (prebuilt->sel_graph) {
		que_graph_free_recursive(prebuilt->sel_graph);
	}
	
	if (prebuilt->upd_graph) {
		que_graph_free_recursive(prebuilt->upd_graph);
	}
	
	if (prebuilt->blob_heap) {
		mem_heap_free(prebuilt->blob_heap);
	}

	if (prebuilt->old_vers_heap) {
		mem_heap_free(prebuilt->old_vers_heap);
	}
	
	for (i = 0; i < MYSQL_FETCH_CACHE_SIZE; i++) {
		if (prebuilt->fetch_cache[i] != NULL) {

			if ((ROW_PREBUILT_FETCH_MAGIC_N !=
			    mach_read_from_4((prebuilt->fetch_cache[i]) - 4))
			    || (ROW_PREBUILT_FETCH_MAGIC_N !=
			    mach_read_from_4((prebuilt->fetch_cache[i])
			    			+ prebuilt->mysql_row_len))) {
				fputs(
			"InnoDB: Error: trying to free a corrupt\n"
			"InnoDB: fetch buffer.\n", stderr);

				mem_analyze_corruption(
						prebuilt->fetch_cache[i]);

				ut_error;
			}

			mem_free((prebuilt->fetch_cache[i]) - 4);
		}
	}

	dict_table_decrement_handle_count(prebuilt->table);

	mem_heap_free(prebuilt->heap);
}

/*************************************************************************
Updates the transaction pointers in query graphs stored in the prebuilt
struct. */

void
row_update_prebuilt_trx(
/*====================*/
					/* out: prebuilt dtuple */
	row_prebuilt_t*	prebuilt,	/* in: prebuilt struct in MySQL
					handle */
	trx_t*		trx)		/* in: transaction handle */
{	
	if (trx->magic_n != TRX_MAGIC_N) {
		fprintf(stderr,
		"InnoDB: Error: trying to use a corrupt\n"
		"InnoDB: trx handle. Magic n %lu\n",
		trx->magic_n);

		mem_analyze_corruption((byte*)trx);

		ut_error;
	}

	if (prebuilt->magic_n != ROW_PREBUILT_ALLOCATED) {
		fprintf(stderr,
		"InnoDB: Error: trying to use a corrupt\n"
		"InnoDB: table handle. Magic n %lu, table name ",
		prebuilt->magic_n);
		ut_print_name(stderr, prebuilt->table->name);
		putc('\n', stderr);

		mem_analyze_corruption((byte*)prebuilt);

		ut_error;
	}

	prebuilt->trx = trx;

	if (prebuilt->ins_graph) {
		prebuilt->ins_graph->trx = trx;
	}

	if (prebuilt->upd_graph) {
		prebuilt->upd_graph->trx = trx;
	}

	if (prebuilt->sel_graph) {
		prebuilt->sel_graph->trx = trx;
	}	
}

/*************************************************************************
Gets pointer to a prebuilt dtuple used in insertions. If the insert graph
has not yet been built in the prebuilt struct, then this function first
builds it. */
static
dtuple_t*
row_get_prebuilt_insert_row(
/*========================*/
					/* out: prebuilt dtuple */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in MySQL
					handle */
{
	ins_node_t*	node;
	dtuple_t*	row;
	dict_table_t*	table	= prebuilt->table;
	ulint		i;

	ut_ad(prebuilt && table && prebuilt->trx);
	
	if (prebuilt->ins_node == NULL) {

		/* Not called before for this handle: create an insert node
		and query graph to the prebuilt struct */

		node = ins_node_create(INS_DIRECT, table, prebuilt->heap);
		
		prebuilt->ins_node = node;

		if (prebuilt->ins_upd_rec_buff == NULL) {
			prebuilt->ins_upd_rec_buff = mem_heap_alloc(
						prebuilt->heap,
						prebuilt->mysql_row_len);
		}
		
		row = dtuple_create(prebuilt->heap,
					dict_table_get_n_cols(table));

		dict_table_copy_types(row, table);

		/* We init the value of every field to the SQL NULL to avoid
		a debug assertion from failing */

		for (i = 0; i < dtuple_get_n_fields(row); i++) {
		    
		        dtuple_get_nth_field(row, i)->len = UNIV_SQL_NULL;
		}

		ins_node_set_new_row(node, row);

		prebuilt->ins_graph =
			que_node_get_parent(
				pars_complete_graph_for_exec(node,
							prebuilt->trx,
							prebuilt->heap));
		prebuilt->ins_graph->state = QUE_FORK_ACTIVE;
	}

	return(prebuilt->ins_node->row);	
}

/*************************************************************************
Updates the table modification counter and calculates new estimates
for table and index statistics if necessary. */
UNIV_INLINE
void
row_update_statistics_if_needed(
/*============================*/
	dict_table_t*	table)	/* in: table */
{
	ulint	counter;
	
	counter = table->stat_modified_counter;

	table->stat_modified_counter = counter + 1;

	/* Calculate new statistics if 1 / 16 of table has been modified
	since the last time a statistics batch was run, or if
	stat_modified_counter > 2 000 000 000 (to avoid wrap-around).
	We calculate statistics at most every 16th round, since we may have
	a counter table which is very small and updated very often. */

	if (counter > 2000000000
	    || ((ib_longlong)counter > 16 + table->stat_n_rows / 16)) {

		dict_update_statistics(table);
	}	
}
		  	
/*************************************************************************
Unlocks an AUTO_INC type lock possibly reserved by trx. */

void		  	
row_unlock_table_autoinc_for_mysql(
/*===============================*/
	trx_t*	trx)	/* in: transaction */
{
	if (!trx->auto_inc_lock) {

		return;
	}

	lock_table_unlock_auto_inc(trx);
}

/*************************************************************************
Sets an AUTO_INC type lock on the table mentioned in prebuilt. The
AUTO_INC lock gives exclusive access to the auto-inc counter of the
table. The lock is reserved only for the duration of an SQL statement.
It is not compatible with another AUTO_INC or exclusive lock on the
table. */

int
row_lock_table_autoinc_for_mysql(
/*=============================*/
					/* out: error code or DB_SUCCESS */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in the MySQL
					table handle */
{
	trx_t*		trx 		= prebuilt->trx;
	ins_node_t*	node		= prebuilt->ins_node;
	que_thr_t*	thr;
	ulint		err;
	ibool		was_lock_wait;
	
	ut_ad(trx);
	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	
	if (trx->auto_inc_lock) {

		return(DB_SUCCESS);
	}

	trx->op_info = (char *) "setting auto-inc lock";

	if (node == NULL) {
		row_get_prebuilt_insert_row(prebuilt);
		node = prebuilt->ins_node;
	}

	/* We use the insert query graph as the dummy graph needed
	in the lock module call */

	thr = que_fork_get_first_thr(prebuilt->ins_graph);

	que_thr_move_to_run_state_for_mysql(thr, trx);

run_again:
	thr->run_node = node;
	thr->prev_node = node;

	/* It may be that the current session has not yet started
	its transaction, or it has been committed: */

	trx_start_if_not_started(trx);

	err = lock_table(0, prebuilt->table, prebuilt->select_lock_type, thr);

	trx->error_state = err;

	if (err != DB_SUCCESS) {
		que_thr_stop_for_mysql(thr);

		was_lock_wait = row_mysql_handle_errors(&err, trx, thr, NULL);

		if (was_lock_wait) {
			goto run_again;
		}

		trx->op_info = (char *) "";

		return(err);
	}

	que_thr_stop_for_mysql_no_error(thr, trx);

	trx->op_info = (char *) "";

	return((int) err);
}

/*************************************************************************
Unlocks a table lock possibly reserved by trx. */

void		  	
row_unlock_table_for_mysql(
/*=======================*/
	trx_t*	trx)	/* in: transaction */
{
	if (!trx->n_tables_locked) {

		return;
	}

	mutex_enter(&kernel_mutex);
	lock_release_tables_off_kernel(trx);
	mutex_exit(&kernel_mutex);
}
/*************************************************************************
Sets a table lock on the table mentioned in prebuilt. */

int
row_lock_table_for_mysql(
/*=====================*/
					/* out: error code or DB_SUCCESS */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in the MySQL
					table handle */
{
	trx_t*		trx 		= prebuilt->trx;
	que_thr_t*	thr;
	ulint		err;
	ibool		was_lock_wait;
	
	ut_ad(trx);
	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());

	trx->op_info = (char *) "setting table lock";

	if (prebuilt->sel_graph == NULL) {
		/* Build a dummy select query graph */
		row_prebuild_sel_graph(prebuilt);
	}

	/* We use the select query graph as the dummy graph needed
	in the lock module call */

	thr = que_fork_get_first_thr(prebuilt->sel_graph);

	que_thr_move_to_run_state_for_mysql(thr, trx);

run_again:
	thr->run_node = thr;
	thr->prev_node = thr->common.parent;

	/* It may be that the current session has not yet started
	its transaction, or it has been committed: */

	trx_start_if_not_started(trx);

	err = lock_table(LOCK_TABLE_EXP, prebuilt->table,
		prebuilt->select_lock_type, thr);

	trx->error_state = err;

	if (err != DB_SUCCESS) {
		que_thr_stop_for_mysql(thr);

		was_lock_wait = row_mysql_handle_errors(&err, trx, thr, NULL);

		if (was_lock_wait) {
			goto run_again;
		}

		trx->op_info = (char *) "";

		return(err);
	}

	que_thr_stop_for_mysql_no_error(thr, trx);
		
	trx->op_info = (char *) "";

	return((int) err);	
}
					
/*************************************************************************
Does an insert for MySQL. */

int
row_insert_for_mysql(
/*=================*/
					/* out: error code or DB_SUCCESS */
	byte*		mysql_rec,	/* in: row in the MySQL format */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in MySQL
					handle */
{
	trx_savept_t	savept;
	que_thr_t*	thr;
	ulint		err;
	ibool		was_lock_wait;
	trx_t*		trx 		= prebuilt->trx;
	ins_node_t*	node		= prebuilt->ins_node;
	
	ut_ad(trx);
	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	
	if (prebuilt->magic_n != ROW_PREBUILT_ALLOCATED) {
		fprintf(stderr,
		"InnoDB: Error: trying to free a corrupt\n"
		"InnoDB: table handle. Magic n %lu, table name ",
		prebuilt->magic_n);
		ut_print_name(stderr, prebuilt->table->name);
		putc('\n', stderr);

		mem_analyze_corruption((byte*)prebuilt);

		ut_error;
	}

	if (srv_created_new_raw || srv_force_recovery) {
		fputs(
		"InnoDB: A new raw disk partition was initialized or\n"
		"InnoDB: innodb_force_recovery is on: we do not allow\n"
		"InnoDB: database modifications by the user. Shut down\n"
		"InnoDB: mysqld and edit my.cnf so that newraw is replaced\n"
		"InnoDB: with raw, and innodb_force_... is removed.\n",
			stderr);

		return(DB_ERROR);
	}

	trx->op_info = (char *) "inserting";

	trx_start_if_not_started(trx);

	if (node == NULL) {
		row_get_prebuilt_insert_row(prebuilt);
		node = prebuilt->ins_node;
	}

	row_mysql_convert_row_to_innobase(node->row, prebuilt, mysql_rec);
	
	savept = trx_savept_take(trx);
	
	thr = que_fork_get_first_thr(prebuilt->ins_graph);

	if (prebuilt->sql_stat_start) {
		node->state = INS_NODE_SET_IX_LOCK;
		prebuilt->sql_stat_start = FALSE;
	} else {
		node->state = INS_NODE_ALLOC_ROW_ID;
	}
	
	que_thr_move_to_run_state_for_mysql(thr, trx);

run_again:
	thr->run_node = node;
	thr->prev_node = node;

	row_ins_step(thr);
	
	err = trx->error_state;

	if (err != DB_SUCCESS) {
		que_thr_stop_for_mysql(thr);

		was_lock_wait = row_mysql_handle_errors(&err, trx, thr,
								&savept);
		if (was_lock_wait) {
			goto run_again;
		}

		trx->op_info = (char *) "";

		return(err);
	}

	que_thr_stop_for_mysql_no_error(thr, trx);
	
	prebuilt->table->stat_n_rows++;

	srv_n_rows_inserted++;
	
	if (prebuilt->table->stat_n_rows == 0) {
		/* Avoid wrap-over */
		prebuilt->table->stat_n_rows--;
	}	

	row_update_statistics_if_needed(prebuilt->table);
	trx->op_info = (char *) "";

	return((int) err);
}

/*************************************************************************
Builds a dummy query graph used in selects. */

void
row_prebuild_sel_graph(
/*===================*/
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in MySQL
					handle */
{
	sel_node_t*	node;

	ut_ad(prebuilt && prebuilt->trx);
	
	if (prebuilt->sel_graph == NULL) {

		node = sel_node_create(prebuilt->heap);
				
		prebuilt->sel_graph =
			que_node_get_parent(
				pars_complete_graph_for_exec(node,
							prebuilt->trx,
							prebuilt->heap));

		prebuilt->sel_graph->state = QUE_FORK_ACTIVE;
	}
}

/*************************************************************************
Creates an query graph node of 'update' type to be used in the MySQL
interface. */

upd_node_t*
row_create_update_node_for_mysql(
/*=============================*/
				/* out, own: update node */
	dict_table_t*	table,	/* in: table to update */
	mem_heap_t*	heap)	/* in: mem heap from which allocated */
{
	upd_node_t*	node;

	node = upd_node_create(heap);
		
	node->in_mysql_interface = TRUE;
	node->is_delete = FALSE;
	node->searched_update = FALSE;
	node->select_will_do_update = FALSE;
	node->select = NULL;
	node->pcur = btr_pcur_create_for_mysql();
	node->table = table;

	node->update = upd_create(dict_table_get_n_cols(table), heap);

	node->update_n_fields = dict_table_get_n_cols(table);
	
	UT_LIST_INIT(node->columns);
	node->has_clust_rec_x_lock = TRUE;
	node->cmpl_info = 0;

	node->table_sym = NULL;
	node->col_assign_list = NULL;

	return(node);
}

/*************************************************************************
Gets pointer to a prebuilt update vector used in updates. If the update
graph has not yet been built in the prebuilt struct, then this function
first builds it. */

upd_t*
row_get_prebuilt_update_vector(
/*===========================*/
					/* out: prebuilt update vector */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in MySQL
					handle */
{
	dict_table_t*	table	= prebuilt->table;
	upd_node_t*	node;

	ut_ad(prebuilt && table && prebuilt->trx);
	
	if (prebuilt->upd_node == NULL) {

		/* Not called before for this handle: create an update node
		and query graph to the prebuilt struct */

		node = row_create_update_node_for_mysql(table, prebuilt->heap);

		prebuilt->upd_node = node;
		
		prebuilt->upd_graph =
			que_node_get_parent(
				pars_complete_graph_for_exec(node,
							prebuilt->trx,
							prebuilt->heap));
		prebuilt->upd_graph->state = QUE_FORK_ACTIVE;
	}

	return(prebuilt->upd_node->update);
}

/*************************************************************************
Does an update or delete of a row for MySQL. */

int
row_update_for_mysql(
/*=================*/
					/* out: error code or DB_SUCCESS */
	byte*		mysql_rec,	/* in: the row to be updated, in
					the MySQL format */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in MySQL
					handle */
{
	trx_savept_t	savept;
	ulint		err;
	que_thr_t*	thr;
	ibool		was_lock_wait;
	dict_index_t*	clust_index; 
/*	ulint		ref_len; */
	upd_node_t*	node;
	dict_table_t*	table		= prebuilt->table;
	trx_t*		trx		= prebuilt->trx;

	ut_ad(prebuilt && trx);
	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	UT_NOT_USED(mysql_rec);
	
	if (prebuilt->magic_n != ROW_PREBUILT_ALLOCATED) {
		fprintf(stderr,
		"InnoDB: Error: trying to free a corrupt\n"
		"InnoDB: table handle. Magic n %lu, table name ",
		prebuilt->magic_n);
		ut_print_name(stderr, prebuilt->table->name);
		putc('\n', stderr);

		mem_analyze_corruption((byte*)prebuilt);

		ut_error;
	}

	if (srv_created_new_raw || srv_force_recovery) {
		fputs(
		"InnoDB: A new raw disk partition was initialized or\n"
		"InnoDB: innodb_force_recovery is on: we do not allow\n"
		"InnoDB: database modifications by the user. Shut down\n"
		"InnoDB: mysqld and edit my.cnf so that newraw is replaced\n"
		"InnoDB: with raw, and innodb_force_... is removed.\n",
			stderr);

		return(DB_ERROR);
	}

	trx->op_info = (char *) "updating or deleting";

	trx_start_if_not_started(trx);

	node = prebuilt->upd_node;

	clust_index = dict_table_get_first_index(table);

	if (prebuilt->pcur->btr_cur.index == clust_index) {
		btr_pcur_copy_stored_position(node->pcur, prebuilt->pcur);
	} else {
		btr_pcur_copy_stored_position(node->pcur,
							prebuilt->clust_pcur);
	}
		
	ut_a(node->pcur->rel_pos == BTR_PCUR_ON);
	 	
	/* MySQL seems to call rnd_pos before updating each row it
	has cached: we can get the correct cursor position from
	prebuilt->pcur; NOTE that we cannot build the row reference
	from mysql_rec if the clustered index was automatically
	generated for the table: MySQL does not know anything about
	the row id used as the clustered index key */

	savept = trx_savept_take(trx);
	
	thr = que_fork_get_first_thr(prebuilt->upd_graph);

	node->state = UPD_NODE_UPDATE_CLUSTERED;

	ut_ad(!prebuilt->sql_stat_start);

	que_thr_move_to_run_state_for_mysql(thr, trx);

run_again:
	thr->run_node = node;
	thr->prev_node = node;

	row_upd_step(thr);

	err = trx->error_state;

	if (err != DB_SUCCESS) {
		que_thr_stop_for_mysql(thr);
		
		if (err == DB_RECORD_NOT_FOUND) {
			trx->error_state = DB_SUCCESS;
			trx->op_info = (char *) "";

			return((int) err);
		}
	
		was_lock_wait = row_mysql_handle_errors(&err, trx, thr,
								&savept);
		if (was_lock_wait) {
			goto run_again;
		}

		trx->op_info = (char *) "";

		return(err);
	}

	que_thr_stop_for_mysql_no_error(thr, trx);

	if (node->is_delete) {
		if (prebuilt->table->stat_n_rows > 0) {
			prebuilt->table->stat_n_rows--;
		}

		srv_n_rows_deleted++;
	} else {
		srv_n_rows_updated++;
	}

	row_update_statistics_if_needed(prebuilt->table);

	trx->op_info = (char *) "";

	return((int) err);
}

/**************************************************************************
Does a cascaded delete or set null in a foreign key operation. */

ulint
row_update_cascade_for_mysql(
/*=========================*/
				/* out: error code or DB_SUCCESS */
	que_thr_t*	thr,	/* in: query thread */
	upd_node_t*	node,	/* in: update node used in the cascade
				or set null operation */
	dict_table_t*	table)	/* in: table where we do the operation */
{
	ulint	err;
	trx_t*	trx;

	trx = thr_get_trx(thr);
run_again:
	thr->run_node = node;
	thr->prev_node = node;

	row_upd_step(thr);

	err = trx->error_state;

	/* Note that the cascade node is a subnode of another InnoDB
	query graph node. We do a normal lock wait in this node, but
	all errors are handled by the parent node. */

	if (err == DB_LOCK_WAIT) {
		/* Handle lock wait here */
	
		que_thr_stop_for_mysql(thr);

		srv_suspend_mysql_thread(thr);

		/* Note that a lock wait may also end in a lock wait timeout,
		or this transaction is picked as a victim in selective
		deadlock resolution */

		if (trx->error_state != DB_SUCCESS) {

			return(trx->error_state);
		}

		/* Retry operation after a normal lock wait */
		
		goto run_again;
	}

	if (err != DB_SUCCESS) {

		return(err);
	}

	if (node->is_delete) {
		if (table->stat_n_rows > 0) {
			table->stat_n_rows--;
		}

		srv_n_rows_deleted++;
	} else {
		srv_n_rows_updated++;
	}

	row_update_statistics_if_needed(table);

	return(err);
}

/*************************************************************************
Checks if a table is such that we automatically created a clustered
index on it (on row id). */

ibool
row_table_got_default_clust_index(
/*==============================*/
	dict_table_t*	table)
{
	dict_index_t*	clust_index;

	clust_index = dict_table_get_first_index(table);

	if (dtype_get_mtype(dict_index_get_nth_type(clust_index, 0))
	 							== DATA_SYS) {
	 	return(TRUE);
	}

	return(FALSE);
}

/*************************************************************************
Calculates the key number used inside MySQL for an Innobase index. We have
to take into account if we generated a default clustered index for the table */

ulint
row_get_mysql_key_number_for_index(
/*===============================*/
	dict_index_t*	index)
{
	dict_index_t*	ind;
	ulint		i;

	ut_a(index);

	i = 0;
	ind = dict_table_get_first_index(index->table);

	while (index != ind) {
		ind = dict_table_get_next_index(ind);
		i++;
	}

	if (row_table_got_default_clust_index(index->table)) {
		ut_a(i > 0);
		i--;
	}

	return(i);
}

/*************************************************************************
Recovers an orphaned tmp table inside InnoDB by renaming it. In the table
name #sql becomes rsql, and "_recover_innodb_tmp_table" is catenated to
the end of name. table->name should be of the form
"dbname/rsql..._recover_innodb_tmp_table". This renames a table whose
name is "#sql..." */
static
int
row_mysql_recover_tmp_table(
/*========================*/
				/* out: error code or DB_SUCCESS */
	dict_table_t*	table,	/* in: table definition */
	trx_t*		trx)	/* in: transaction handle */
{
	const char*	ptr	= strstr(table->name, "/rsql");

	if (!ptr) {
		/* table name does not begin with "/rsql" */
		trx_commit_for_mysql(trx);
		return(DB_ERROR);
	}
	else {
		int	status;
		int	namelen = strlen(table->name);
		char*	old_name = mem_strdupl(table->name, namelen);
		/* replace "rsql" with "#sql" */
		old_name[ptr - table->name + 1] = '#';
		/* remove "_recover_innodb_tmp_table" suffix */
		ut_ad(namelen > (int) sizeof S_recover_innodb_tmp_table);
		ut_ad(!strcmp(old_name + namelen + 1 -
			sizeof S_recover_innodb_tmp_table,
			S_recover_innodb_tmp_table));
		old_name[namelen + 1 - sizeof S_recover_innodb_tmp_table] = 0;
		status = row_rename_table_for_mysql(old_name,
						table->name, trx);
		mem_free(old_name);
		return(status);
	}
}

/*************************************************************************
Locks the data dictionary in shared mode from modifications, for performing
foreign key check, rollback, or other operation invisible to MySQL. */

void
row_mysql_freeze_data_dictionary(
/*=============================*/
	trx_t*	trx)	/* in: transaction */
{
	ut_a(trx->dict_operation_lock_mode == 0);
	
	rw_lock_s_lock(&dict_operation_lock);

	trx->dict_operation_lock_mode = RW_S_LATCH;
}

/*************************************************************************
Unlocks the data dictionary shared lock. */

void
row_mysql_unfreeze_data_dictionary(
/*===============================*/
	trx_t*	trx)	/* in: transaction */
{
	ut_a(trx->dict_operation_lock_mode == RW_S_LATCH);

	rw_lock_s_unlock(&dict_operation_lock);

	trx->dict_operation_lock_mode = 0;
}

/*************************************************************************
Locks the data dictionary exclusively for performing a table create or other
data dictionary modification operation. */

void
row_mysql_lock_data_dictionary(
/*===========================*/
	trx_t*	trx)	/* in: transaction */
{
	ut_a(trx->dict_operation_lock_mode == 0);
	
	/* Serialize data dictionary operations with dictionary mutex:
	no deadlocks or lock waits can occur then in these operations */

	rw_lock_x_lock(&dict_operation_lock);
	trx->dict_operation_lock_mode = RW_X_LATCH;

	mutex_enter(&(dict_sys->mutex));
}

/*************************************************************************
Unlocks the data dictionary exclusive lock. */

void
row_mysql_unlock_data_dictionary(
/*=============================*/
	trx_t*	trx)	/* in: transaction */
{
	ut_a(trx->dict_operation_lock_mode == RW_X_LATCH);

	/* Serialize data dictionary operations with dictionary mutex:
	no deadlocks can occur then in these operations */

	mutex_exit(&(dict_sys->mutex));
	rw_lock_x_unlock(&dict_operation_lock);

	trx->dict_operation_lock_mode = 0;
}

/*************************************************************************
Does a table creation operation for MySQL.  If the name of the table
to be created is equal with one of the predefined magic table names,
then this also starts printing the corresponding monitor output by
the master thread. */
int
row_create_table_for_mysql(
/*=======================*/
				/* out: error code or DB_SUCCESS */
	dict_table_t*	table,	/* in: table definition */
	trx_t*		trx)	/* in: transaction handle */
{
	tab_node_t*	node;
	mem_heap_t*	heap;
	que_thr_t*	thr;
	ulint		namelen;
	ulint		err;

	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
#ifdef UNIV_SYNC_DEBUG
	ut_ad(rw_lock_own(&dict_operation_lock, RW_LOCK_EX));
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(trx->dict_operation_lock_mode == RW_X_LATCH);
	
	if (srv_created_new_raw) {
		fputs(
		"InnoDB: A new raw disk partition was initialized or\n"
		"InnoDB: innodb_force_recovery is on: we do not allow\n"
		"InnoDB: database modifications by the user. Shut down\n"
		"InnoDB: mysqld and edit my.cnf so that newraw is replaced\n"
		"InnoDB: with raw, and innodb_force_... is removed.\n",
		stderr);

		trx_commit_for_mysql(trx);

		return(DB_ERROR);
	}

	trx->op_info = (char *) "creating table";
	
	if (row_mysql_is_system_table(table->name)) {

		fprintf(stderr,
    "InnoDB: Error: trying to create a MySQL system table %s of type InnoDB.\n"
    "InnoDB: MySQL system tables must be of the MyISAM type!\n",
		table->name);

		trx_commit_for_mysql(trx);

		return(DB_ERROR);
	}

	trx_start_if_not_started(trx);

	if (row_mysql_is_recovered_tmp_table(table->name)) {

		/* MySQL prevents accessing of tables whose name begins
		with #sql, that is temporary tables. If mysqld crashes in
		the middle of an ALTER TABLE, we may get an orphaned
		#sql-table in the tablespace. We have here a special
		mechanism to recover such tables by renaming them to
		rsql... */
 				
		return(row_mysql_recover_tmp_table(table, trx));
	}

	namelen = strlen(table->name) + 1;

	if (namelen == sizeof S_innodb_monitor
			&& !memcmp(table->name, S_innodb_monitor,
				sizeof S_innodb_monitor)) {

		/* Table equals "innodb_monitor":
		start monitor prints */
 				
		srv_print_innodb_monitor = TRUE;

		/* The lock timeout monitor thread also takes care
		of InnoDB monitor prints */

		os_event_set(srv_lock_timeout_thread_event);
	} else if (namelen == sizeof S_innodb_lock_monitor
			&& !memcmp(table->name, S_innodb_lock_monitor,
				sizeof S_innodb_lock_monitor)) {

		srv_print_innodb_monitor = TRUE;
		srv_print_innodb_lock_monitor = TRUE;
		os_event_set(srv_lock_timeout_thread_event);
	} else if (namelen == sizeof S_innodb_tablespace_monitor
			&& !memcmp(table->name, S_innodb_tablespace_monitor,
				sizeof S_innodb_tablespace_monitor)) {

		srv_print_innodb_tablespace_monitor = TRUE;
		os_event_set(srv_lock_timeout_thread_event);
	} else if (namelen == sizeof S_innodb_table_monitor
			&& !memcmp(table->name, S_innodb_table_monitor,
				sizeof S_innodb_table_monitor)) {

		srv_print_innodb_table_monitor = TRUE;
		os_event_set(srv_lock_timeout_thread_event);
	} else if (namelen == sizeof S_innodb_mem_validate
			&& !memcmp(table->name, S_innodb_mem_validate,
				sizeof S_innodb_mem_validate)) {
	        /* We define here a debugging feature intended for
		developers */

		fputs("Validating InnoDB memory:\n"
		 "to use this feature you must compile InnoDB with\n"
		 "UNIV_MEM_DEBUG defined in univ.i and the server must be\n"
		 "quiet because allocation from a mem heap is not protected\n"
		"by any semaphore.\n", stderr);
#ifdef UNIV_MEM_DEBUG
		ut_a(mem_validate());
		fputs("Memory validated\n", stderr);
#else /* UNIV_MEM_DEBUG */
		fputs("Memory NOT validated (recompile with UNIV_MEM_DEBUG)\n",
			stderr);
#endif /* UNIV_MEM_DEBUG */
	}

	heap = mem_heap_create(512);

	trx->dict_operation = TRUE;
	
	node = tab_create_graph_create(table, heap);

	thr = pars_complete_graph_for_exec(node, trx, heap);

	ut_a(thr == que_fork_start_command(que_node_get_parent(thr)));
	que_run_threads(thr);

	err = trx->error_state;

	if (err != DB_SUCCESS) {
		/* We have special error handling here */
		
		trx->error_state = DB_SUCCESS;
		
		trx_general_rollback_for_mysql(trx, FALSE, NULL);

		if (err == DB_OUT_OF_FILE_SPACE) {
			fputs("InnoDB: Warning: cannot create table ", stderr);
			ut_print_name(stderr, table->name);
			fputs(" because tablespace full\n", stderr);
		     	row_drop_table_for_mysql(table->name, trx, FALSE);
		} else {
		       	ut_a(err == DB_DUPLICATE_KEY);

	    		ut_print_timestamp(stderr);

			fputs("  InnoDB: Error: table ", stderr);
			ut_print_name(stderr, table->name);
			fputs(" already exists in InnoDB internal\n"
     "InnoDB: data dictionary. Have you deleted the .frm file\n"
     "InnoDB: and not used DROP TABLE? Have you used DROP DATABASE\n"
     "InnoDB: for InnoDB tables in MySQL version <= 3.23.43?\n"
     "InnoDB: See the Restrictions section of the InnoDB manual.\n"
     "InnoDB: You can drop the orphaned table inside InnoDB by\n"
     "InnoDB: creating an InnoDB table with the same name in another\n"
     "InnoDB: database and moving the .frm file to the current database.\n"
     "InnoDB: Then MySQL thinks the table exists, and DROP TABLE will\n"
     "InnoDB: succeed.\n"
     "InnoDB: You can look for further help from section 15.1 of\n"
     "InnoDB: http://www.innodb.com/ibman.php\n", stderr);
		}

		trx->error_state = DB_SUCCESS;
	}

	que_graph_free((que_t*) que_node_get_parent(thr));

	trx->op_info = (char *) "";

	return((int) err);
}

/*************************************************************************
Does an index creation operation for MySQL. TODO: currently failure
to create an index results in dropping the whole table! This is no problem
currently as all indexes must be created at the same time as the table. */

int
row_create_index_for_mysql(
/*=======================*/
					/* out: error number or DB_SUCCESS */
	dict_index_t*	index,		/* in: index definition */
	trx_t*		trx)		/* in: transaction handle */
{
	ind_node_t*	node;
	mem_heap_t*	heap;
	que_thr_t*	thr;
	ulint		err;
	ulint		i, j;
	
#ifdef UNIV_SYNC_DEBUG
	ut_ad(rw_lock_own(&dict_operation_lock, RW_LOCK_EX));
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	
	trx->op_info = (char *) "creating index";

	/* Check that the same column does not appear twice in the index.
	Starting from 4.0.14, InnoDB should be able to cope with that, but
	safer not to allow them. */

	for (i = 0; i < dict_index_get_n_fields(index); i++) {
		for (j = 0; j < i; j++) {
			if (0 == ut_strcmp(
			      dict_index_get_nth_field(index, j)->name,
			      dict_index_get_nth_field(index, i)->name)) {

				ut_print_timestamp(stderr);

				fputs("  InnoDB: Error: column ", stderr);
				ut_print_name(stderr,
				dict_index_get_nth_field(index, i)->name);
				fputs(" appears twice in ", stderr);
				dict_index_name_print(stderr, index);
				fputs("\n"
				"InnoDB: This is not allowed in InnoDB.\n",
					stderr);

				err = DB_COL_APPEARS_TWICE_IN_INDEX;

				goto error_handling;
			}
		}
	}

	trx_start_if_not_started(trx);

	if (row_mysql_is_recovered_tmp_table(index->table_name)) {

		return(DB_SUCCESS);
	}

	heap = mem_heap_create(512);

	trx->dict_operation = TRUE;

	node = ind_create_graph_create(index, heap);

	thr = pars_complete_graph_for_exec(node, trx, heap);

	ut_a(thr == que_fork_start_command(que_node_get_parent(thr)));
	que_run_threads(thr);

 	err = trx->error_state;

	que_graph_free((que_t*) que_node_get_parent(thr));

error_handling:

	if (err != DB_SUCCESS) {
		/* We have special error handling here */
		
		trx->error_state = DB_SUCCESS;

		trx_general_rollback_for_mysql(trx, FALSE, NULL);

		row_drop_table_for_mysql(index->table_name, trx, FALSE);

		trx->error_state = DB_SUCCESS;
	}
	
	trx->op_info = (char *) "";

	return((int) err);
}

/*************************************************************************
Scans a table create SQL string and adds to the data dictionary
the foreign key constraints declared in the string. This function
should be called after the indexes for a table have been created.
Each foreign key constraint must be accompanied with indexes in
bot participating tables. The indexes are allowed to contain more
fields than mentioned in the constraint. Check also that foreign key
constraints which reference this table are ok. */

int
row_table_add_foreign_constraints(
/*==============================*/
				/* out: error code or DB_SUCCESS */
	trx_t*	trx,		/* in: transaction */
	char*	sql_string,	/* in: table create statement where
				foreign keys are declared like:
				FOREIGN KEY (a, b) REFERENCES table2(c, d),
				table2 can be written also with the database
				name before it: test.table2 */
	char*	name)		/* in: table full name in the normalized form
				database_name/table_name */
{
	ulint	err;

#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
	ut_ad(rw_lock_own(&dict_operation_lock, RW_LOCK_EX));
#endif /* UNIV_SYNC_DEBUG */
	ut_a(sql_string);
	
	trx->op_info = (char *) "adding foreign keys";

	trx_start_if_not_started(trx);

	if (row_mysql_is_recovered_tmp_table(name)) {

		return(DB_SUCCESS);
	}

	trx->dict_operation = TRUE;

	err = dict_create_foreign_constraints(trx, sql_string, name);

	if (err == DB_SUCCESS) {
		/* Check that also referencing constraints are ok */
		err = dict_load_foreigns(name);
	}

	if (err != DB_SUCCESS) {
		/* We have special error handling here */
		
		trx->error_state = DB_SUCCESS;

		trx_general_rollback_for_mysql(trx, FALSE, NULL);

		row_drop_table_for_mysql(name, trx, FALSE);

		trx->error_state = DB_SUCCESS;
	}

	return((int) err);
}

/*************************************************************************
Drops a table for MySQL as a background operation. MySQL relies on Unix
in ALTER TABLE to the fact that the table handler does not remove the
table before all handles to it has been removed. Furhermore, the MySQL's
call to drop table must be non-blocking. Therefore we do the drop table
as a background operation, which is taken care of by the master thread
in srv0srv.c. */
static
int
row_drop_table_for_mysql_in_background(
/*===================================*/
			/* out: error code or DB_SUCCESS */
	char*	name)	/* in: table name */
{
	ulint	error;
	trx_t*	trx;

	trx = trx_allocate_for_background();

/*	fputs("InnoDB: Error: Dropping table ", stderr);
	ut_print_name(stderr, name);
	fputs(" in background drop list\n", stderr); */

  	/* Drop the table in InnoDB */

  	error = row_drop_table_for_mysql(name, trx, FALSE);

	if (error != DB_SUCCESS) {
		ut_print_timestamp(stderr);
		fputs("  InnoDB: Error: Dropping table ", stderr);
		ut_print_name(stderr, name);
		fputs(" in background drop list failed\n", stderr);
	}
  	
	/* Flush the log to reduce probability that the .frm files and
	the InnoDB data dictionary get out-of-sync if the user runs
	with innodb_flush_log_at_trx_commit = 0 */
	
	log_buffer_flush_to_disk();

  	trx_commit_for_mysql(trx);

  	trx_free_for_background(trx);

	return(DB_SUCCESS);
}

/*************************************************************************
The master thread in srv0srv.c calls this regularly to drop tables which
we must drop in background after queries to them have ended. Such lazy
dropping of tables is needed in ALTER TABLE on Unix. */

ulint
row_drop_tables_for_mysql_in_background(void)
/*=========================================*/
					/* out: how many tables dropped
					+ remaining tables in list */
{
	row_mysql_drop_t*	drop;
	dict_table_t*		table;
	ulint			n_tables;
	ulint			n_tables_dropped = 0;
loop:	
	mutex_enter(&kernel_mutex);

	if (!row_mysql_drop_list_inited) {

		UT_LIST_INIT(row_mysql_drop_list);
		row_mysql_drop_list_inited = TRUE;
	}

	drop = UT_LIST_GET_FIRST(row_mysql_drop_list);
	
	n_tables = UT_LIST_GET_LEN(row_mysql_drop_list);

	mutex_exit(&kernel_mutex);

	if (drop == NULL) {

		return(n_tables + n_tables_dropped);
	}

	mutex_enter(&(dict_sys->mutex));
	table = dict_table_get_low(drop->table_name);
	mutex_exit(&(dict_sys->mutex));

	if (table == NULL) {
	        /* If for some reason the table has already been dropped
		through some other mechanism, do not try to drop it */

	        goto already_dropped;
	}

	if (table->n_mysql_handles_opened > 0
				|| table->n_foreign_key_checks_running > 0) {

		return(n_tables + n_tables_dropped);
	}

	n_tables_dropped++;
							
	row_drop_table_for_mysql_in_background(drop->table_name);

already_dropped:
	mutex_enter(&kernel_mutex);

	UT_LIST_REMOVE(row_mysql_drop_list, row_mysql_drop_list, drop);

        ut_print_timestamp(stderr);
	fputs("  InnoDB: Dropped table ", stderr);
	ut_print_name(stderr, drop->table_name);
	fputs(" in background drop queue.\n", stderr);

	mem_free(drop->table_name);

	mem_free(drop);

	mutex_exit(&kernel_mutex);

	goto loop;
}

/*************************************************************************
Get the background drop list length. NOTE: the caller must own the kernel
mutex! */

ulint
row_get_background_drop_list_len_low(void)
/*======================================*/
					/* out: how many tables in list */
{
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&kernel_mutex));
#endif /* UNIV_SYNC_DEBUG */

	if (!row_mysql_drop_list_inited) {

		UT_LIST_INIT(row_mysql_drop_list);
		row_mysql_drop_list_inited = TRUE;
	}
	
	return(UT_LIST_GET_LEN(row_mysql_drop_list));
}

/*************************************************************************
Adds a table to the list of tables which the master thread drops in
background. We need this on Unix because in ALTER TABLE MySQL may call
drop table even if the table has running queries on it. */
static
void
row_add_table_to_background_drop_list(
/*==================================*/
	dict_table_t*	table)	/* in: table */
{
	row_mysql_drop_t*	drop;
	
	drop = mem_alloc(sizeof(row_mysql_drop_t));

	drop->table_name = mem_strdup(table->name);

	mutex_enter(&kernel_mutex);

	if (!row_mysql_drop_list_inited) {

		UT_LIST_INIT(row_mysql_drop_list);
		row_mysql_drop_list_inited = TRUE;
	}

	UT_LIST_ADD_LAST(row_mysql_drop_list, row_mysql_drop_list, drop);
	
/*	fputs("InnoDB: Adding table ", stderr);
	ut_print_name(stderr, drop->table_name);
	fputs(" to background drop list\n", stderr); */

	mutex_exit(&kernel_mutex);
}

/*************************************************************************
Drops a table for MySQL.  If the name of the table to be dropped is equal
with one of the predefined magic table names, then this also stops printing
the corresponding monitor output by the master thread. */

int
row_drop_table_for_mysql(
/*=====================*/
			/* out: error code or DB_SUCCESS */
	char*	name,	/* in: table name */
	trx_t*	trx,	/* in: transaction handle */
	ibool	drop_db)/* in: TRUE=dropping whole database */
{
	dict_foreign_t*	foreign;
	dict_table_t*	table;
	que_thr_t*	thr;
	que_t*		graph;
	ulint		err;
	ulint		namelen;
	ibool		locked_dictionary	= FALSE;
	char*		quoted_name;
	char*		sql;
	/* We use the private SQL parser of Innobase to generate the
	query graphs needed in deleting the dictionary data from system
	tables in Innobase. Deleting a row from SYS_INDEXES table also
	frees the file segments of the B-tree associated with the index. */
	static const char str1[] =
	"PROCEDURE DROP_TABLE_PROC () IS\n"
	"table_name CHAR;\n"
	"sys_foreign_id CHAR;\n"
	"table_id CHAR;\n"
	"index_id CHAR;\n"
	"foreign_id CHAR;\n"
	"found INT;\n"
	"BEGIN\n"
	"table_name := ";
	static const char str2[] =
	";\n"
	"SELECT ID INTO table_id\n"
	"FROM SYS_TABLES\n"
	"WHERE NAME = table_name;\n"
	"IF (SQL % NOTFOUND) THEN\n"
	"	COMMIT WORK;\n"
	"	RETURN;\n"
	"END IF;\n"
	"found := 1;\n"
	"SELECT ID INTO sys_foreign_id\n"
	"FROM SYS_TABLES\n"
	"WHERE NAME = 'SYS_FOREIGN';\n"
	"IF (SQL % NOTFOUND) THEN\n"
	"	found := 0;\n"
	"END IF;\n"
	"IF (table_name = 'SYS_FOREIGN') THEN\n"
	"	found := 0;\n"
	"END IF;\n"
	"IF (table_name = 'SYS_FOREIGN_COLS') THEN\n"
	"	found := 0;\n"
	"END IF;\n"
	"WHILE found = 1 LOOP\n"
	"	SELECT ID INTO foreign_id\n"
	"	FROM SYS_FOREIGN\n"
	"	WHERE FOR_NAME = table_name;\n"	
	"	IF (SQL % NOTFOUND) THEN\n"
	"		found := 0;\n"
	"	ELSE"
	"		DELETE FROM SYS_FOREIGN_COLS WHERE ID = foreign_id;\n"
	"		DELETE FROM SYS_FOREIGN WHERE ID = foreign_id;\n"
	"	END IF;\n"
	"END LOOP;\n"
	"found := 1;\n"
	"WHILE found = 1 LOOP\n"
	"	SELECT ID INTO index_id\n"
	"	FROM SYS_INDEXES\n"
	"	WHERE TABLE_ID = table_id;\n"	
	"	IF (SQL % NOTFOUND) THEN\n"
	"		found := 0;\n"
	"	ELSE"
	"		DELETE FROM SYS_FIELDS WHERE INDEX_ID = index_id;\n"
	"		DELETE FROM SYS_INDEXES WHERE ID = index_id\n"
	"					 AND TABLE_ID = table_id;\n"
	"	END IF;\n"
	"END LOOP;\n"
	"DELETE FROM SYS_COLUMNS WHERE TABLE_ID = table_id;\n"
	"DELETE FROM SYS_TABLES WHERE ID = table_id;\n"
	"COMMIT WORK;\n"
	"END;\n";

	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	ut_a(name != NULL);

	if (srv_created_new_raw) {
		fputs(
		"InnoDB: A new raw disk partition was initialized or\n"
		"InnoDB: innodb_force_recovery is on: we do not allow\n"
		"InnoDB: database modifications by the user. Shut down\n"
		"InnoDB: mysqld and edit my.cnf so that newraw is replaced\n"
		"InnoDB: with raw, and innodb_force_... is removed.\n",
		stderr);

		return(DB_ERROR);
	}

	trx->op_info = (char *) "dropping table";

	trx_start_if_not_started(trx);

	namelen = strlen(name) + 1;

	if (namelen == sizeof S_innodb_monitor
			&& !memcmp(name, S_innodb_monitor,
				sizeof S_innodb_monitor)) {

		/* Table name equals "innodb_monitor":
		stop monitor prints */
 				
		srv_print_innodb_monitor = FALSE;
		srv_print_innodb_lock_monitor = FALSE;
	} else if (namelen == sizeof S_innodb_lock_monitor
			&& !memcmp(name, S_innodb_lock_monitor,
				sizeof S_innodb_lock_monitor)) {

		srv_print_innodb_monitor = FALSE;
		srv_print_innodb_lock_monitor = FALSE;
	} else if (namelen == sizeof S_innodb_tablespace_monitor
			&& !memcmp(name, S_innodb_tablespace_monitor,
				sizeof S_innodb_tablespace_monitor)) {

		srv_print_innodb_tablespace_monitor = FALSE;
	} else if (namelen == sizeof S_innodb_table_monitor
			&& !memcmp(name, S_innodb_table_monitor,
				sizeof S_innodb_table_monitor)) {

		srv_print_innodb_table_monitor = FALSE;
	}

	quoted_name = mem_strdupq(name, '\'');
	namelen = strlen(quoted_name);
	sql = mem_alloc((sizeof str1) + (sizeof str2) - 2 + 1 + namelen);
	memcpy(sql, str1, (sizeof str1) - 1);
	memcpy(sql + (sizeof str1) - 1, quoted_name, namelen);
	memcpy(sql + (sizeof str1) - 1 + namelen, str2, sizeof str2);

	/* Serialize data dictionary operations with dictionary mutex:
	no deadlocks can occur then in these operations */

	if (trx->dict_operation_lock_mode != RW_X_LATCH) {
		/* Prevent foreign key checks etc. while we are dropping the
		table */

		row_mysql_lock_data_dictionary(trx);

		locked_dictionary = TRUE;
	}

#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
	ut_ad(rw_lock_own(&dict_operation_lock, RW_LOCK_EX));
#endif /* UNIV_SYNC_DEBUG */
	
	graph = pars_sql(sql);

	ut_a(graph);
	mem_free(sql);

	graph->trx = trx;
	trx->graph = NULL;

	graph->fork_type = QUE_FORK_MYSQL_INTERFACE;

	table = dict_table_get_low(name);

	if (!table) {
		err = DB_TABLE_NOT_FOUND;
	    	ut_print_timestamp(stderr);

		fputs("  InnoDB: Error: table ", stderr);
		ut_print_name(stderr, name);
		fputs(" does not exist in the InnoDB internal\n"
     	"InnoDB: data dictionary though MySQL is trying to drop it.\n"
     	"InnoDB: Have you copied the .frm file of the table to the\n"
	"InnoDB: MySQL database directory from another database?\n"
	"InnoDB: You can look for further help from section 15.1 of\n"
	"InnoDB: http://www.innodb.com/ibman.php\n", stderr);
		goto funct_exit;
	}

	/* Check if the table is referenced by foreign key constraints from
	some other table (not the table itself) */

	foreign = UT_LIST_GET_FIRST(table->referenced_list);
	
	while (foreign && foreign->foreign_table == table) {
		foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
	}

	if (foreign && trx->check_foreigns &&
		!(drop_db && dict_tables_have_same_db(
			name, foreign->foreign_table_name))) {
		FILE*	ef	= dict_foreign_err_file;

		/* We only allow dropping a referenced table if
		FOREIGN_KEY_CHECKS is set to 0 */

		err = DB_CANNOT_DROP_CONSTRAINT;

		mutex_enter(&dict_foreign_err_mutex);
		rewind(ef);
		ut_print_timestamp(ef);

		fputs("  Cannot drop table ", ef);
		ut_print_name(ef, name);
		fputs("\n"
			"because it is referenced by ", ef);
		ut_print_name(ef, foreign->foreign_table_name);
		putc('\n', ef);
		mutex_exit(&dict_foreign_err_mutex);

		goto funct_exit;
	}

	if (table->n_mysql_handles_opened > 0) {

	        ut_print_timestamp(stderr);
		fputs("	 InnoDB: Warning: MySQL is trying to drop table ",
			stderr);
		ut_print_name(stderr, table->name);
		fputs("\n"
		  "InnoDB: though there are still open handles to it.\n"
		  "InnoDB: Adding the table to the background drop queue.\n",
			stderr);

		row_add_table_to_background_drop_list(table);

		err = DB_SUCCESS;

		goto funct_exit;
	}

	if (table->n_foreign_key_checks_running > 0) {

	        ut_print_timestamp(stderr);
		fputs("	 InnoDB: You are trying to drop table ", stderr);
		ut_print_name(stderr, table->name);
		fputs("\n"
		  "InnoDB: though there are foreign key check running on it.\n"
		  "InnoDB: Adding the table to the background drop queue.\n",
			stderr);

		row_add_table_to_background_drop_list(table);

		err = DB_SUCCESS;

		goto funct_exit;
	}
	
	/* Remove any locks there are on the table or its records */
	
	lock_reset_all_on_table(table);

	trx->dict_operation = TRUE;
	trx->table_id = table->id;

	ut_a(thr = que_fork_start_command(graph));

	que_run_threads(thr);

	err = trx->error_state;

	if (err != DB_SUCCESS) {
		ut_a(err == DB_OUT_OF_FILE_SPACE);

		err = DB_MUST_GET_MORE_FILE_SPACE;
		
		row_mysql_handle_errors(&err, trx, thr, NULL);

		ut_error;
	} else {
		dict_table_remove_from_cache(table);

		if (dict_load_table(name) != NULL) {
			ut_print_timestamp(stderr);
			fputs("  InnoDB: Error: dropping of table ",
				stderr);
			ut_print_name(stderr, name);
			fputs(" failed!\n", stderr);
			err = DB_ERROR;
		}
	}
funct_exit:

	if (locked_dictionary) {
		row_mysql_unlock_data_dictionary(trx);	
	}

	que_graph_free(graph);
	
  	trx_commit_for_mysql(trx);

	trx->op_info = (char *) "";

	srv_wake_master_thread();

	return((int) err);
}

/*************************************************************************
Drops a database for MySQL. */

int
row_drop_database_for_mysql(
/*========================*/
			/* out: error code or DB_SUCCESS */
	char*	name,	/* in: database name which ends to '/' */
	trx_t*	trx)	/* in: transaction handle */
{
        dict_table_t* table;
	char*	table_name;
	int	err	= DB_SUCCESS;
	
	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	ut_a(name != NULL);
	ut_a(name[strlen(name) - 1] == '/');
	
	trx->op_info = (char *) "dropping database";
	
	trx_start_if_not_started(trx);
loop:
	row_mysql_lock_data_dictionary(trx);

	while ((table_name = dict_get_first_table_name_in_db(name))) {
		ut_a(strcmp(table_name, name) == 0);

		table = dict_table_get_low(table_name);

		ut_a(table);

		/* Wait until MySQL does not have any queries running on
		the table */

		if (table->n_mysql_handles_opened > 0) {
			row_mysql_unlock_data_dictionary(trx);

			ut_print_timestamp(stderr);
			fputs(
	"  InnoDB: Warning: MySQL is trying to drop database ", stderr);
			ut_print_name(stderr, name);
			fputs("\n"
	"InnoDB: though there are still open handles to table ", stderr);
			ut_print_name(stderr, table_name);
			fputs(".\n", stderr);

		        os_thread_sleep(1000000);

		        mem_free(table_name);

		        goto loop;
		}

		err = row_drop_table_for_mysql(table_name, trx, TRUE);

		mem_free(table_name);

		if (err != DB_SUCCESS) {
			fputs("InnoDB: DROP DATABASE ", stderr);
			ut_print_name(stderr, name);
			fprintf(stderr, " failed with error %lu for table ",
				(ulint) err);
			ut_print_name(stderr, table_name);
			putc('\n', stderr);
			break;
		}
	}

	row_mysql_unlock_data_dictionary(trx);
	
	trx_commit_for_mysql(trx);

	trx->op_info = (char *) "";

	return(err);
}

/*************************************************************************
Checks if a table name contains the string "/#sql" which denotes temporary
tables in MySQL. */
static
ibool
row_is_mysql_tmp_table_name(
/*========================*/
				/* out: TRUE if temporary table */
	const char*	name)	/* in: table name in the form
				'database/tablename' */
{
	return(strstr(name, "/#sql") != NULL);
}

/*************************************************************************
Renames a table for MySQL. */

int
row_rename_table_for_mysql(
/*=======================*/
				/* out: error code or DB_SUCCESS */
	char*	old_name,	/* in: old table name */
	char*	new_name,	/* in: new table name */
	trx_t*	trx)		/* in: transaction handle */
{
	dict_table_t*	table;
	que_thr_t*	thr;
	que_t*		graph			= NULL;
	ulint		err;
	/* We use the private SQL parser of Innobase to generate the
	query graphs needed in deleting the dictionary data from system
	tables in Innobase. Deleting a row from SYS_INDEXES table also
	frees the file segments of the B-tree associated with the index. */
	static const char str1[] =
	"PROCEDURE RENAME_TABLE_PROC () IS\n"
	"new_table_name CHAR;\n"
	"old_table_name CHAR;\n"
	"gen_constr_prefix CHAR;\n"
	"new_db_name CHAR;\n"
	"foreign_id CHAR;\n"
	"new_foreign_id CHAR;\n"
	"old_db_name_len INT;\n"
	"old_t_name_len INT;\n"
	"new_db_name_len INT;\n"
	"id_len INT;\n"
	"found INT;\n"
	"BEGIN\n"
	"new_table_name := '";
	static const char str2[] =
	"';\nold_table_name := '";
	static const char str3[] =
	"';\n"
	"UPDATE SYS_TABLES SET NAME = new_table_name\n"
	"WHERE NAME = old_table_name;\n";
	static const char str4a1[] = /* drop some constraints of tmp tables */
	"DELETE FROM SYS_FOREIGN_COLS WHERE ID = '";
	static const char str4a2[] = "';\n"
	"DELETE FROM SYS_FOREIGN WHERE ID = '";
	static const char str4a3[] = "';\n";
	static const char str4b[] = /* rename all constraints */
	"found := 1;\n"
	"old_db_name_len := INSTR(old_table_name, '/') - 1;\n"
	"new_db_name_len := INSTR(new_table_name, '/') - 1;\n"
	"new_db_name := SUBSTR(new_table_name, 0, new_db_name_len);\n"
	"old_t_name_len := LENGTH(old_table_name);\n"
	"gen_constr_prefix := CONCAT(old_table_name, '_ibfk_');\n"
	"WHILE found = 1 LOOP\n"
	"	SELECT ID INTO foreign_id\n"
	"	FROM SYS_FOREIGN\n"
	"	WHERE FOR_NAME = old_table_name;\n"	
	"	IF (SQL % NOTFOUND) THEN\n"
	"	 found := 0;\n"
	"	ELSE\n"
	"	 UPDATE SYS_FOREIGN\n"
	"	 SET FOR_NAME = new_table_name\n"
	"	 WHERE ID = foreign_id;\n"
	"	 id_len := LENGTH(foreign_id);\n"
	"	 IF (INSTR(foreign_id, '/') > 0) THEN\n"
	"	 	IF (INSTR(foreign_id,\n"
	"				gen_constr_prefix) > 0)\n"
	"		THEN\n"
	"		  new_foreign_id :=\n"
	"		    CONCAT(new_table_name,\n"
	"			SUBSTR(foreign_id, old_t_name_len,\n"
	"			      	 id_len - old_t_name_len));\n"
	"		ELSE\n"
	"		  new_foreign_id :=\n"
	"		    CONCAT(new_db_name,\n"
	"			SUBSTR(foreign_id,\n"
	"				old_db_name_len,\n"
	"				 id_len - old_db_name_len));\n"
	"		END IF;\n"
	"		UPDATE SYS_FOREIGN\n"
	"		SET ID = new_foreign_id\n"
	"		WHERE ID = foreign_id;\n"
	"		UPDATE SYS_FOREIGN_COLS\n"
	"		SET ID = new_foreign_id\n"
	"		WHERE ID = foreign_id;\n"
	"	 END IF;\n"
	"	END IF;\n"
	"END LOOP;\n"
	"UPDATE SYS_FOREIGN SET REF_NAME = new_table_name\n"
	"WHERE REF_NAME = old_table_name;\n";
	static const char str5[] =
	"END;\n";

	mem_heap_t*	heap			= NULL;
	const char**	constraints_to_drop	= NULL;
	ulint		n_constraints_to_drop	= 0;
        ibool           recovering_temp_table   = FALSE;
	ulint		len;
	ulint		i;
	/* length of database name; 0 if not renaming to a temporary table */
	ulint		db_name_len;
	char*		sql;
	char*		sqlend;

	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
	ut_a(old_name != NULL);
	ut_a(new_name != NULL);

	if (srv_created_new_raw || srv_force_recovery) {
		fputs(
		"InnoDB: A new raw disk partition was initialized or\n"
		"InnoDB: innodb_force_recovery is on: we do not allow\n"
		"InnoDB: database modifications by the user. Shut down\n"
		"InnoDB: mysqld and edit my.cnf so that newraw is replaced\n"
		"InnoDB: with raw, and innodb_force_... is removed.\n",
		stderr);

  		trx_commit_for_mysql(trx);
		return(DB_ERROR);
	}
	
	if (row_mysql_is_system_table(new_name)) {
	    	
		fprintf(stderr,
    "InnoDB: Error: trying to create a MySQL system table %s of type InnoDB.\n"
    "InnoDB: MySQL system tables must be of the MyISAM type!\n",
		new_name);

  		trx_commit_for_mysql(trx);
		return(DB_ERROR);
	}

	trx->op_info = (char *) "renaming table";
	trx_start_if_not_started(trx);

	if (row_mysql_is_recovered_tmp_table(new_name)) {

                recovering_temp_table = TRUE;
        } else {
		/* Serialize data dictionary operations with dictionary mutex:
		no deadlocks can occur then in these operations */

		row_mysql_lock_data_dictionary(trx);
	}

	table = dict_table_get_low(old_name);

	if (!table) {
		err = DB_TABLE_NOT_FOUND;

		goto funct_exit;
	}

	/* calculate the length of the SQL string */
	len = (sizeof str1) + (sizeof str2) + (sizeof str3) + (sizeof str5) - 4
		+ ut_strlenq(new_name, '\'') + ut_strlenq(old_name, '\'');

	if (row_is_mysql_tmp_table_name(new_name)) {
		db_name_len = dict_get_db_name_len(old_name) + 1;

		/* MySQL is doing an ALTER TABLE command and it renames the
		original table to a temporary table name. We want to preserve
		the original foreign key constraint definitions despite the
		name change. An exception is those constraints for which
		the ALTER TABLE contained DROP FOREIGN KEY <foreign key id>.*/

		heap = mem_heap_create(100);
		
		err = dict_foreign_parse_drop_constraints(heap, trx,
					table,
					&n_constraints_to_drop,
					&constraints_to_drop);
		if (err != DB_SUCCESS) {

			goto funct_exit;
		}

		/* reserve space for all database names */
		len += 2 * n_constraints_to_drop
			* (ut_strlenq(old_name, '\'')
			- ut_strlenq(old_name + db_name_len, '\''));

		for (i = 0; i < n_constraints_to_drop; i++) {
			ulint	addlen
				= 2 * ut_strlenq(constraints_to_drop[i], '\'')
				+ ((sizeof str4a1) + (sizeof str4a2)
				+ (sizeof str4a3) - 3);
			if (!strchr(constraints_to_drop[i], '/')) {
				addlen *= 2;
			}
			len += addlen;
		}
	} else {
		db_name_len = 0;
		len += (sizeof str4b) - 1;
	}

	sql = sqlend = mem_alloc(len + 1);
	memcpy(sql, str1, (sizeof str1) - 1);
	sqlend += (sizeof str1) - 1;
	sqlend = ut_strcpyq(sqlend, '\'', new_name);
	memcpy(sqlend, str2, (sizeof str2) - 1);
	sqlend += (sizeof str2) - 1;
	sqlend = ut_strcpyq(sqlend, '\'', old_name);
	memcpy(sqlend, str3, (sizeof str3) - 1);
	sqlend += (sizeof str3) - 1;

	if (db_name_len) {
		/* Internally, old format < 4.0.18 constraints have as the
		constraint id <number>_<number>, while new format constraints
		have <databasename>/<constraintname>. */

		for (i = 0; i < n_constraints_to_drop; i++) {
			memcpy(sqlend, str4a1, (sizeof str4a1) - 1);
			sqlend += (sizeof str4a1) - 1;
			sqlend = ut_memcpyq(sqlend, '\'',
				old_name, db_name_len);
			sqlend = ut_strcpyq(sqlend, '\'',
				constraints_to_drop[i]);
			memcpy(sqlend, str4a2, (sizeof str4a2) - 1);
			sqlend += (sizeof str4a2) - 1;
			sqlend = ut_memcpyq(sqlend, '\'',
				old_name, db_name_len);
                        sqlend = ut_strcpyq(sqlend, '\'',
				constraints_to_drop[i]);
			memcpy(sqlend, str4a3, (sizeof str4a3) - 1);
			sqlend += (sizeof str4a3) - 1;

			if (!strchr(constraints_to_drop[i], '/')) {
				/* If this happens to be an old format
				constraint, let us delete it. Since all new
				format constraints contain '/', it does no
				harm to run these DELETEs anyway. */

				memcpy(sqlend, str4a1, (sizeof str4a1) - 1);
				sqlend += (sizeof str4a1) - 1;
				sqlend = ut_strcpyq(sqlend, '\'',
					constraints_to_drop[i]);
				memcpy(sqlend, str4a2, (sizeof str4a2) - 1);
				sqlend += (sizeof str4a2) - 1;
                        	sqlend = ut_strcpyq(sqlend, '\'',
					constraints_to_drop[i]);
				memcpy(sqlend, str4a3, (sizeof str4a3) - 1);
				sqlend += (sizeof str4a3) - 1;
			}
		}
	}
	else {
		memcpy(sqlend, str4b, (sizeof str4b) - 1);
		sqlend += (sizeof str4b) - 1;
	}

	memcpy(sqlend, str5, sizeof str5);
	sqlend += sizeof str5;

	ut_a(sqlend == sql + len + 1);
	
	graph = pars_sql(sql);

	ut_a(graph);
	mem_free(sql);

	graph->trx = trx;
	trx->graph = NULL;

	graph->fork_type = QUE_FORK_MYSQL_INTERFACE;

	ut_a(thr = que_fork_start_command(graph));

	que_run_threads(thr);

	err = trx->error_state;

	if (err != DB_SUCCESS) {
		if (err == DB_DUPLICATE_KEY) {
	    		ut_print_timestamp(stderr);

			fputs("  InnoDB: Error: table ", stderr);
			ut_print_name(stderr, new_name);
			fputs(" exists in the InnoDB internal data\n"
     "InnoDB: dictionary though MySQL is trying rename table ", stderr);
			ut_print_name(stderr, old_name);
			fputs(" to it.\n"
     "InnoDB: Have you deleted the .frm file and not used DROP TABLE?\n"
     "InnoDB: You can look for further help from section 15.1 of\n"
     "InnoDB: http://www.innodb.com/ibman.php\n"
     "InnoDB: If table ", stderr);
			ut_print_name(stderr, new_name);
			fputs(
		" is a temporary table #sql..., then it can be that\n"
     "InnoDB: there are still queries running on the table, and it will be\n"
     "InnoDB: dropped automatically when the queries end.\n"
     "InnoDB: You can drop the orphaned table inside InnoDB by\n"
     "InnoDB: creating an InnoDB table with the same name in another\n"
     "InnoDB: database and moving the .frm file to the current database.\n"
     "InnoDB: Then MySQL thinks the table exists, and DROP TABLE will\n"
     "InnoDB: succeed.\n", stderr);
		}

		trx->error_state = DB_SUCCESS;
		trx_general_rollback_for_mysql(trx, FALSE, NULL);
		trx->error_state = DB_SUCCESS;
	} else {
		ut_a(dict_table_rename_in_cache(table, new_name,
				!row_is_mysql_tmp_table_name(new_name)));

		if (row_is_mysql_tmp_table_name(old_name)) {

			/* MySQL is doing an ALTER TABLE command and it
			renames the created temporary table to the name
			of the original table. In the ALTER TABLE we maybe
			created some FOREIGN KEY constraints for the temporary
			table. But we want to load also the foreign key
			constraint definitions for the original table name. */

			err = dict_load_foreigns(new_name);

			if (err != DB_SUCCESS) {

	    			ut_print_timestamp(stderr);

				fputs("  InnoDB: Error: in ALTER TABLE table ",
					stderr);
				ut_print_name(stderr, new_name);
				fputs("\n"
     "InnoDB: has or is referenced in foreign key constraints\n"
     "InnoDB: which are not compatible with the new table definition.\n",
					stderr);
     
				ut_a(dict_table_rename_in_cache(table,
							old_name, FALSE));
						
				trx->error_state = DB_SUCCESS;
				trx_general_rollback_for_mysql(trx, FALSE,
									NULL);
				trx->error_state = DB_SUCCESS;
			}
		}
	}
funct_exit:
	if (!recovering_temp_table) {		
		row_mysql_unlock_data_dictionary(trx);
	}

	if (graph) {
		que_graph_free(graph);
	}

	if (heap) {
		mem_heap_free(heap);
	}
	
  	trx_commit_for_mysql(trx);

	trx->op_info = (char *) "";

	return((int) err);
}

/*************************************************************************
Checks that the index contains entries in an ascending order, unique
constraint is not broken, and calculates the number of index entries
in the read view of the current transaction. */
static
ibool
row_scan_and_check_index(
/*=====================*/
					/* out: TRUE if ok */
	row_prebuilt_t*	prebuilt,	/* in: prebuilt struct in MySQL */
	dict_index_t*	index,		/* in: index */
	ulint*		n_rows)		/* out: number of entries seen in the
					current consistent read */
{
	mem_heap_t*	heap;
	dtuple_t*	prev_entry = NULL;
	ulint		matched_fields;
	ulint		matched_bytes;
	byte*		buf;
	ulint		ret;
	rec_t*		rec;
	ibool		is_ok	= TRUE;
	int		cmp;
	ibool		contains_null;
	ulint		i;
	
	*n_rows = 0;
	
	buf = mem_alloc(UNIV_PAGE_SIZE);
	heap = mem_heap_create(100);
	
	/* Make a dummy template in prebuilt, which we will use
	in scanning the index entries */

	prebuilt->index = index;
	prebuilt->sql_stat_start = TRUE;
	prebuilt->template_type = ROW_MYSQL_DUMMY_TEMPLATE;
	prebuilt->n_template = 0;
	prebuilt->need_to_access_clustered = FALSE;

 	dtuple_set_n_fields(prebuilt->search_tuple, 0);

	prebuilt->select_lock_type = LOCK_NONE;

	ret = row_search_for_mysql(buf, PAGE_CUR_G, prebuilt, 0, 0);
loop:
	if (ret != DB_SUCCESS) {

		mem_free(buf);
		mem_heap_free(heap);

		return(is_ok);
	}

	*n_rows = *n_rows + 1;
	
	/* row_search... returns the index record in buf, record origin offset
	within buf stored in the first 4 bytes, because we have built a dummy
	template */
	
	rec = buf + mach_read_from_4(buf);

	if (prev_entry != NULL) {
		matched_fields = 0;
		matched_bytes = 0;
	
		cmp = cmp_dtuple_rec_with_match(prev_entry, rec,
						&matched_fields,
						&matched_bytes);
		contains_null = FALSE;

		/* In a unique secondary index we allow equal key values if
		they contain SQL NULLs */

	        for (i = 0;
                     i < dict_index_get_n_ordering_defined_by_user(index);
		     i++) {
	                if (UNIV_SQL_NULL == dfield_get_len(
                                      dtuple_get_nth_field(prev_entry, i))) {

                        	contains_null = TRUE;
	                }
	        }

		if (cmp > 0) {
			fputs("InnoDB: index records in a wrong order in ",
				stderr);
		not_ok:
			dict_index_name_print(stderr, index);
			fputs("\n"
				"InnoDB: prev record ", stderr);
			dtuple_print(stderr, prev_entry);
			fputs("\n"
				"InnoDB: record ", stderr);
			rec_print(stderr, rec);
			putc('\n', stderr);
			is_ok = FALSE;
		} else if ((index->type & DICT_UNIQUE)
			   && !contains_null
			   && matched_fields >=
			   dict_index_get_n_ordering_defined_by_user(index)) {

			fputs("InnoDB: duplicate key in ", stderr);
			goto not_ok;
		}
	}

	mem_heap_empty(heap);
	
	prev_entry = row_rec_to_index_entry(ROW_COPY_DATA, index, rec, heap);

	ret = row_search_for_mysql(buf, PAGE_CUR_G, prebuilt, 0, ROW_SEL_NEXT);

	goto loop;	
}

/*************************************************************************
Checks a table for corruption. */

ulint
row_check_table_for_mysql(
/*======================*/
					/* out: DB_ERROR or DB_SUCCESS */
	row_prebuilt_t*	prebuilt)	/* in: prebuilt struct in MySQL
					handle */
{
	dict_table_t*	table		= prebuilt->table;
	dict_index_t*	index;
	ulint		n_rows;
	ulint		n_rows_in_table	= ULINT_UNDEFINED;
	ulint		ret 		= DB_SUCCESS;
	ulint		old_isolation_level;
	
	prebuilt->trx->op_info = (char *) "checking table";

	old_isolation_level = prebuilt->trx->isolation_level;

	/* We must run the index record counts at an isolation level
	>= READ COMMITTED, because a dirty read can see a wrong number
	of records in some index; to play safe, we use always
	REPEATABLE READ here */

	prebuilt->trx->isolation_level = TRX_ISO_REPEATABLE_READ;
	
	index = dict_table_get_first_index(table);

	while (index != NULL) {
		/* fputs("Validating index ", stderr);
		ut_print_name(stderr, index->name);
		putc('\n', stderr); */
	
		if (!btr_validate_tree(index->tree)) {
			ret = DB_ERROR;
		} else {
			if (!row_scan_and_check_index(prebuilt,
							index, &n_rows)) {
				ret = DB_ERROR;
			}

			/* fprintf(stderr, "%lu entries in index ", n_rows);
			ut_print_name(stderr, index->name);
			putc('\n', stderr); */

			if (index == dict_table_get_first_index(table)) {
				n_rows_in_table = n_rows;
			} else if (n_rows != n_rows_in_table) {

				ret = DB_ERROR;

				fputs("InnoDB: Error: ", stderr);
				dict_index_name_print(stderr, index);
				fprintf(stderr,
				" contains %lu entries, should be %lu\n",
					n_rows, n_rows_in_table);
			}
		}

		index = dict_table_get_next_index(index);
	}

	/* Restore the original isolation level */
	prebuilt->trx->isolation_level = old_isolation_level;
	
	/* We validate also the whole adaptive hash index for all tables
	at every CHECK TABLE */

	if (!btr_search_validate()) {

		ret = DB_ERROR;
	}

	prebuilt->trx->op_info = (char *) "";

	return(ret);
}