mariadb/storage/innobase/dict/dict0crea.c

/*****************************************************************************

Copyright (c) 1996, 2010, Innobase Oy. All Rights Reserved.

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; version 2 of the License.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA

*****************************************************************************/

/**************************************************//**
@file dict/dict0crea.c
Database object creation

Created 1/8/1996 Heikki Tuuri
*******************************************************/

#include "dict0crea.h"

#ifdef UNIV_NONINL
#include "dict0crea.ic"
#endif

#include "btr0pcur.h"
#include "btr0btr.h"
#include "page0page.h"
#include "mach0data.h"
#include "dict0boot.h"
#include "dict0dict.h"
#include "que0que.h"
#include "row0ins.h"
#include "row0mysql.h"
#include "pars0pars.h"
#include "trx0roll.h"
#include "usr0sess.h"
#include "ut0vec.h"

/*****************************************************************//**
Based on a table object, this function builds the entry to be inserted
in the SYS_TABLES system table.
@return	the tuple which should be inserted */
static
dtuple_t*
dict_create_sys_tables_tuple(
/*=========================*/
	const dict_table_t*	table,	/*!< in: table */
	mem_heap_t*		heap)	/*!< in: memory heap from
					which the memory for the built
					tuple is allocated */
{
	dict_table_t*	sys_tables;
	dtuple_t*	entry;
	dfield_t*	dfield;
	byte*		ptr;

	ut_ad(table);
	ut_ad(heap);

	sys_tables = dict_sys->sys_tables;

	entry = dtuple_create(heap, 8 + DATA_N_SYS_COLS);

	dict_table_copy_types(entry, sys_tables);

	/* 0: NAME -----------------------------*/
	dfield = dtuple_get_nth_field(entry, 0/*NAME*/);

	dfield_set_data(dfield, table->name, ut_strlen(table->name));
	/* 3: ID -------------------------------*/
	dfield = dtuple_get_nth_field(entry, 1/*ID*/);

	ptr = mem_heap_alloc(heap, 8);
	mach_write_to_8(ptr, table->id);

	dfield_set_data(dfield, ptr, 8);
	/* 4: N_COLS ---------------------------*/
	dfield = dtuple_get_nth_field(entry, 2/*N_COLS*/);

#if DICT_TF_COMPACT != 1
#error
#endif

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, table->n_def
			| ((table->flags & DICT_TF_COMPACT) << 31));
	dfield_set_data(dfield, ptr, 4);
	/* 5: TYPE -----------------------------*/
	dfield = dtuple_get_nth_field(entry, 3/*TYPE*/);

	ptr = mem_heap_alloc(heap, 4);
	if (table->flags & (~DICT_TF_COMPACT & ~(~0 << DICT_TF_BITS))) {
		ut_a(table->flags & DICT_TF_COMPACT);
		ut_a(dict_table_get_format(table) >= DICT_TF_FORMAT_ZIP);
		ut_a((table->flags & DICT_TF_ZSSIZE_MASK)
		     <= (DICT_TF_ZSSIZE_MAX << DICT_TF_ZSSIZE_SHIFT));
		ut_a(!(table->flags & (~0 << DICT_TF2_BITS)));
		mach_write_to_4(ptr, table->flags & ~(~0 << DICT_TF_BITS));
	} else {
		mach_write_to_4(ptr, DICT_TABLE_ORDINARY);
	}

	dfield_set_data(dfield, ptr, 4);
	/* 6: MIX_ID (obsolete) ---------------------------*/
	dfield = dtuple_get_nth_field(entry, 4/*MIX_ID*/);

	ptr = mem_heap_zalloc(heap, 8);

	dfield_set_data(dfield, ptr, 8);
	/* 7: MIX_LEN (additional flags) --------------------------*/

	dfield = dtuple_get_nth_field(entry, 5/*MIX_LEN*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, table->flags >> DICT_TF2_SHIFT);

	dfield_set_data(dfield, ptr, 4);
	/* 8: CLUSTER_NAME ---------------------*/
	dfield = dtuple_get_nth_field(entry, 6/*CLUSTER_NAME*/);
	dfield_set_null(dfield); /* not supported */

	/* 9: SPACE ----------------------------*/
	dfield = dtuple_get_nth_field(entry, 7/*SPACE*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, table->space);

	dfield_set_data(dfield, ptr, 4);
	/*----------------------------------*/

	return(entry);
}

/*****************************************************************//**
Based on a table object, this function builds the entry to be inserted
in the SYS_COLUMNS system table.
@return	the tuple which should be inserted */
static
dtuple_t*
dict_create_sys_columns_tuple(
/*==========================*/
	const dict_table_t*	table,	/*!< in: table */
	ulint			i,	/*!< in: column number */
	mem_heap_t*		heap)	/*!< in: memory heap from
					which the memory for the built
					tuple is allocated */
{
	dict_table_t*		sys_columns;
	dtuple_t*		entry;
	const dict_col_t*	column;
	dfield_t*		dfield;
	byte*			ptr;
	const char*		col_name;

	ut_ad(table);
	ut_ad(heap);

	column = dict_table_get_nth_col(table, i);

	sys_columns = dict_sys->sys_columns;

	entry = dtuple_create(heap, 7 + DATA_N_SYS_COLS);

	dict_table_copy_types(entry, sys_columns);

	/* 0: TABLE_ID -----------------------*/
	dfield = dtuple_get_nth_field(entry, 0/*TABLE_ID*/);

	ptr = mem_heap_alloc(heap, 8);
	mach_write_to_8(ptr, table->id);

	dfield_set_data(dfield, ptr, 8);
	/* 1: POS ----------------------------*/
	dfield = dtuple_get_nth_field(entry, 1/*POS*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, i);

	dfield_set_data(dfield, ptr, 4);
	/* 4: NAME ---------------------------*/
	dfield = dtuple_get_nth_field(entry, 2/*NAME*/);

	col_name = dict_table_get_col_name(table, i);
	dfield_set_data(dfield, col_name, ut_strlen(col_name));
	/* 5: MTYPE --------------------------*/
	dfield = dtuple_get_nth_field(entry, 3/*MTYPE*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, column->mtype);

	dfield_set_data(dfield, ptr, 4);
	/* 6: PRTYPE -------------------------*/
	dfield = dtuple_get_nth_field(entry, 4/*PRTYPE*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, column->prtype);

	dfield_set_data(dfield, ptr, 4);
	/* 7: LEN ----------------------------*/
	dfield = dtuple_get_nth_field(entry, 5/*LEN*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, column->len);

	dfield_set_data(dfield, ptr, 4);
	/* 8: PREC ---------------------------*/
	dfield = dtuple_get_nth_field(entry, 6/*PREC*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, 0/* unused */);

	dfield_set_data(dfield, ptr, 4);
	/*---------------------------------*/

	return(entry);
}

/***************************************************************//**
Builds a table definition to insert.
@return	DB_SUCCESS or error code */
static
ulint
dict_build_table_def_step(
/*======================*/
	que_thr_t*	thr,	/*!< in: query thread */
	tab_node_t*	node)	/*!< in: table create node */
{
	dict_table_t*	table;
	dtuple_t*	row;
	ulint		error;
	ulint		flags;
	const char*	path_or_name;
	ibool		is_path;
	mtr_t		mtr;
	ulint		space = 0;
	ibool		file_per_table;

	ut_ad(mutex_own(&(dict_sys->mutex)));

	table = node->table;

	/* Cache the global variable "srv_file_per_table" to
	a local variable before using it. Please note
	"srv_file_per_table" is not under dict_sys mutex
	protection, and could be changed while executing
	this function. So better to cache the current value
	to a local variable, and all future reference to
	"srv_file_per_table" should use this local variable. */
	file_per_table = srv_file_per_table;

	dict_hdr_get_new_id(&table->id, NULL, NULL);

	thr_get_trx(thr)->table_id = table->id;

	if (file_per_table) {
		/* Get a new space id if srv_file_per_table is set */
		dict_hdr_get_new_id(NULL, NULL, &space);

		if (UNIV_UNLIKELY(space == ULINT_UNDEFINED)) {
			return(DB_ERROR);
		}

		/* We create a new single-table tablespace for the table.
		We initially let it be 4 pages:
		- page 0 is the fsp header and an extent descriptor page,
		- page 1 is an ibuf bitmap page,
		- page 2 is the first inode page,
		- page 3 will contain the root of the clustered index of the
		table we create here. */

		if (table->dir_path_of_temp_table) {
			/* We place tables created with CREATE TEMPORARY
			TABLE in the tmp dir of mysqld server */

			path_or_name = table->dir_path_of_temp_table;
			is_path = TRUE;
		} else {
			path_or_name = table->name;
			is_path = FALSE;
		}

		ut_ad(dict_table_get_format(table) <= DICT_TF_FORMAT_MAX);
		ut_ad(!dict_table_zip_size(table)
		      || dict_table_get_format(table) >= DICT_TF_FORMAT_ZIP);

		flags = table->flags & ~(~0 << DICT_TF_BITS);
		error = fil_create_new_single_table_tablespace(
			space, path_or_name, is_path,
			flags == DICT_TF_COMPACT ? 0 : flags,
			FIL_IBD_FILE_INITIAL_SIZE);
		table->space = (unsigned int) space;

		if (error != DB_SUCCESS) {

			return(error);
		}

		mtr_start(&mtr);

		fsp_header_init(table->space, FIL_IBD_FILE_INITIAL_SIZE, &mtr);

		mtr_commit(&mtr);
	} else {
		/* Create in the system tablespace: disallow new features */
		table->flags &= (~0 << DICT_TF_BITS) | DICT_TF_COMPACT;
	}

	row = dict_create_sys_tables_tuple(table, node->heap);

	ins_node_set_new_row(node->tab_def, row);

	return(DB_SUCCESS);
}

/***************************************************************//**
Builds a column definition to insert.
@return	DB_SUCCESS */
static
ulint
dict_build_col_def_step(
/*====================*/
	tab_node_t*	node)	/*!< in: table create node */
{
	dtuple_t*	row;

	row = dict_create_sys_columns_tuple(node->table, node->col_no,
					    node->heap);
	ins_node_set_new_row(node->col_def, row);

	return(DB_SUCCESS);
}

/*****************************************************************//**
Based on an index object, this function builds the entry to be inserted
in the SYS_INDEXES system table.
@return	the tuple which should be inserted */
static
dtuple_t*
dict_create_sys_indexes_tuple(
/*==========================*/
	const dict_index_t*	index,	/*!< in: index */
	mem_heap_t*		heap)	/*!< in: memory heap from
					which the memory for the built
					tuple is allocated */
{
	dict_table_t*	sys_indexes;
	dict_table_t*	table;
	dtuple_t*	entry;
	dfield_t*	dfield;
	byte*		ptr;

	ut_ad(mutex_own(&(dict_sys->mutex)));
	ut_ad(index);
	ut_ad(heap);

	sys_indexes = dict_sys->sys_indexes;

	table = dict_table_get_low(index->table_name);

	entry = dtuple_create(heap, 7 + DATA_N_SYS_COLS);

	dict_table_copy_types(entry, sys_indexes);

	/* 0: TABLE_ID -----------------------*/
	dfield = dtuple_get_nth_field(entry, 0/*TABLE_ID*/);

	ptr = mem_heap_alloc(heap, 8);
	mach_write_to_8(ptr, table->id);

	dfield_set_data(dfield, ptr, 8);
	/* 1: ID ----------------------------*/
	dfield = dtuple_get_nth_field(entry, 1/*ID*/);

	ptr = mem_heap_alloc(heap, 8);
	mach_write_to_8(ptr, index->id);

	dfield_set_data(dfield, ptr, 8);
	/* 4: NAME --------------------------*/
	dfield = dtuple_get_nth_field(entry, 2/*NAME*/);

	dfield_set_data(dfield, index->name, ut_strlen(index->name));
	/* 5: N_FIELDS ----------------------*/
	dfield = dtuple_get_nth_field(entry, 3/*N_FIELDS*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, index->n_fields);

	dfield_set_data(dfield, ptr, 4);
	/* 6: TYPE --------------------------*/
	dfield = dtuple_get_nth_field(entry, 4/*TYPE*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, index->type);

	dfield_set_data(dfield, ptr, 4);
	/* 7: SPACE --------------------------*/

#if DICT_SYS_INDEXES_SPACE_NO_FIELD != 7
#error "DICT_SYS_INDEXES_SPACE_NO_FIELD != 7"
#endif

	dfield = dtuple_get_nth_field(entry, 5/*SPACE*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, index->space);

	dfield_set_data(dfield, ptr, 4);
	/* 8: PAGE_NO --------------------------*/

#if DICT_SYS_INDEXES_PAGE_NO_FIELD != 8
#error "DICT_SYS_INDEXES_PAGE_NO_FIELD != 8"
#endif

	dfield = dtuple_get_nth_field(entry, 6/*PAGE_NO*/);

	ptr = mem_heap_alloc(heap, 4);
	mach_write_to_4(ptr, FIL_NULL);

	dfield_set_data(dfield, ptr, 4);
	/*--------------------------------*/

	return(entry);
}

/*****************************************************************//**
Based on an index object, this function builds the entry to be inserted
in the SYS_FIELDS system table.
@return	the tuple which should be inserted */
static
dtuple_t*
dict_create_sys_fields_tuple(
/*=========================*/
	const dict_index_t*	index,	/*!< in: index */
	ulint			i,	/*!< in: field number */
	mem_heap_t*		heap)	/*!< in: memory heap from
					which the memory for the built
					tuple is allocated */
{
	dict_table_t*	sys_fields;
	dtuple_t*	entry;
	dict_field_t*	field;
	dfield_t*	dfield;
	byte*		ptr;
	ibool		index_contains_column_prefix_field	= FALSE;
	ulint		j;

	ut_ad(index);
	ut_ad(heap);

	for (j = 0; j < index->n_fields; j++) {
		if (dict_index_get_nth_field(index, j)->prefix_len > 0) {
			index_contains_column_prefix_field = TRUE;
			break;
		}
	}

	field = dict_index_get_nth_field(index, i);

	sys_fields = dict_sys->sys_fields;

	entry = dtuple_create(heap, 3 + DATA_N_SYS_COLS);

	dict_table_copy_types(entry, sys_fields);

	/* 0: INDEX_ID -----------------------*/
	dfield = dtuple_get_nth_field(entry, 0/*INDEX_ID*/);

	ptr = mem_heap_alloc(heap, 8);
	mach_write_to_8(ptr, index->id);

	dfield_set_data(dfield, ptr, 8);
	/* 1: POS + PREFIX LENGTH ----------------------------*/

	dfield = dtuple_get_nth_field(entry, 1/*POS*/);

	ptr = mem_heap_alloc(heap, 4);

	if (index_contains_column_prefix_field) {
		/* If there are column prefix fields in the index, then
		we store the number of the field to the 2 HIGH bytes
		and the prefix length to the 2 low bytes, */

		mach_write_to_4(ptr, (i << 16) + field->prefix_len);
	} else {
		/* Else we store the number of the field to the 2 LOW bytes.
		This is to keep the storage format compatible with
		InnoDB versions < 4.0.14. */

		mach_write_to_4(ptr, i);
	}

	dfield_set_data(dfield, ptr, 4);
	/* 4: COL_NAME -------------------------*/
	dfield = dtuple_get_nth_field(entry, 2/*COL_NAME*/);

	dfield_set_data(dfield, field->name,
			ut_strlen(field->name));
	/*---------------------------------*/

	return(entry);
}

/*****************************************************************//**
Creates the tuple with which the index entry is searched for writing the index
tree root page number, if such a tree is created.
@return	the tuple for search */
static
dtuple_t*
dict_create_search_tuple(
/*=====================*/
	const dtuple_t*	tuple,	/*!< in: the tuple inserted in the SYS_INDEXES
				table */
	mem_heap_t*	heap)	/*!< in: memory heap from which the memory for
				the built tuple is allocated */
{
	dtuple_t*	search_tuple;
	const dfield_t*	field1;
	dfield_t*	field2;

	ut_ad(tuple && heap);

	search_tuple = dtuple_create(heap, 2);

	field1 = dtuple_get_nth_field(tuple, 0);
	field2 = dtuple_get_nth_field(search_tuple, 0);

	dfield_copy(field2, field1);

	field1 = dtuple_get_nth_field(tuple, 1);
	field2 = dtuple_get_nth_field(search_tuple, 1);

	dfield_copy(field2, field1);

	ut_ad(dtuple_validate(search_tuple));

	return(search_tuple);
}

/***************************************************************//**
Builds an index definition row to insert.
@return	DB_SUCCESS or error code */
static
ulint
dict_build_index_def_step(
/*======================*/
	que_thr_t*	thr,	/*!< in: query thread */
	ind_node_t*	node)	/*!< in: index create node */
{
	dict_table_t*	table;
	dict_index_t*	index;
	dtuple_t*	row;
	trx_t*		trx;

	ut_ad(mutex_own(&(dict_sys->mutex)));

	trx = thr_get_trx(thr);

	index = node->index;

	table = dict_table_get_low(index->table_name);

	if (table == NULL) {
		return(DB_TABLE_NOT_FOUND);
	}

	trx->table_id = table->id;

	node->table = table;

	ut_ad((UT_LIST_GET_LEN(table->indexes) > 0)
	      || dict_index_is_clust(index));

	dict_hdr_get_new_id(NULL, &index->id, NULL);

	/* Inherit the space id from the table; we store all indexes of a
	table in the same tablespace */

	index->space = table->space;
	node->page_no = FIL_NULL;
	row = dict_create_sys_indexes_tuple(index, node->heap);
	node->ind_row = row;

	ins_node_set_new_row(node->ind_def, row);

	/* Note that the index was created by this transaction. */
	index->trx_id = trx->id;

	return(DB_SUCCESS);
}

/***************************************************************//**
Builds a field definition row to insert.
@return	DB_SUCCESS */
static
ulint
dict_build_field_def_step(
/*======================*/
	ind_node_t*	node)	/*!< in: index create node */
{
	dict_index_t*	index;
	dtuple_t*	row;

	index = node->index;

	row = dict_create_sys_fields_tuple(index, node->field_no, node->heap);

	ins_node_set_new_row(node->field_def, row);

	return(DB_SUCCESS);
}

/***************************************************************//**
Creates an index tree for the index if it is not a member of a cluster.
@return	DB_SUCCESS or DB_OUT_OF_FILE_SPACE */
static
ulint
dict_create_index_tree_step(
/*========================*/
	ind_node_t*	node)	/*!< in: index create node */
{
	dict_index_t*	index;
	dict_table_t*	sys_indexes;
	dict_table_t*	table;
	dtuple_t*	search_tuple;
	ulint		zip_size;
	btr_pcur_t	pcur;
	mtr_t		mtr;

	ut_ad(mutex_own(&(dict_sys->mutex)));

	index = node->index;
	table = node->table;

	sys_indexes = dict_sys->sys_indexes;

	/* Run a mini-transaction in which the index tree is allocated for
	the index and its root address is written to the index entry in
	sys_indexes */

	mtr_start(&mtr);

	search_tuple = dict_create_search_tuple(node->ind_row, node->heap);

	btr_pcur_open(UT_LIST_GET_FIRST(sys_indexes->indexes),
		      search_tuple, PAGE_CUR_L, BTR_MODIFY_LEAF,
		      &pcur, &mtr);

	btr_pcur_move_to_next_user_rec(&pcur, &mtr);

	zip_size = dict_table_zip_size(index->table);

	node->page_no = btr_create(index->type, index->space, zip_size,
				   index->id, index, &mtr);
	/* printf("Created a new index tree in space %lu root page %lu\n",
	index->space, index->page_no); */

	page_rec_write_index_page_no(btr_pcur_get_rec(&pcur),
				     DICT_SYS_INDEXES_PAGE_NO_FIELD,
				     node->page_no, &mtr);
	btr_pcur_close(&pcur);
	mtr_commit(&mtr);

	if (node->page_no == FIL_NULL) {

		return(DB_OUT_OF_FILE_SPACE);
	}

	return(DB_SUCCESS);
}

/*******************************************************************//**
Drops the index tree associated with a row in SYS_INDEXES table. */
UNIV_INTERN
void
dict_drop_index_tree(
/*=================*/
	rec_t*	rec,	/*!< in/out: record in the clustered index
			of SYS_INDEXES table */
	mtr_t*	mtr)	/*!< in: mtr having the latch on the record page */
{
	ulint		root_page_no;
	ulint		space;
	ulint		zip_size;
	const byte*	ptr;
	ulint		len;

	ut_ad(mutex_own(&(dict_sys->mutex)));
	ut_a(!dict_table_is_comp(dict_sys->sys_indexes));
	ptr = rec_get_nth_field_old(rec, DICT_SYS_INDEXES_PAGE_NO_FIELD, &len);

	ut_ad(len == 4);

	root_page_no = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);

	if (root_page_no == FIL_NULL) {
		/* The tree has already been freed */

		return;
	}

	ptr = rec_get_nth_field_old(rec,
				    DICT_SYS_INDEXES_SPACE_NO_FIELD, &len);

	ut_ad(len == 4);

	space = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);
	zip_size = fil_space_get_zip_size(space);

	if (UNIV_UNLIKELY(zip_size == ULINT_UNDEFINED)) {
		/* It is a single table tablespace and the .ibd file is
		missing: do nothing */

		return;
	}

	/* We free all the pages but the root page first; this operation
	may span several mini-transactions */

	btr_free_but_not_root(space, zip_size, root_page_no);

	/* Then we free the root page in the same mini-transaction where
	we write FIL_NULL to the appropriate field in the SYS_INDEXES
	record: this mini-transaction marks the B-tree totally freed */

	/* printf("Dropping index tree in space %lu root page %lu\n", space,
	root_page_no); */
	btr_free_root(space, zip_size, root_page_no, mtr);

	page_rec_write_index_page_no(rec,
				     DICT_SYS_INDEXES_PAGE_NO_FIELD,
				     FIL_NULL, mtr);
}

/*******************************************************************//**
Truncates the index tree associated with a row in SYS_INDEXES table.
@return	new root page number, or FIL_NULL on failure */
UNIV_INTERN
ulint
dict_truncate_index_tree(
/*=====================*/
	dict_table_t*	table,	/*!< in: the table the index belongs to */
	ulint		space,	/*!< in: 0=truncate,
				nonzero=create the index tree in the
				given tablespace */
	btr_pcur_t*	pcur,	/*!< in/out: persistent cursor pointing to
				record in the clustered index of
				SYS_INDEXES table. The cursor may be
				repositioned in this call. */
	mtr_t*		mtr)	/*!< in: mtr having the latch
				on the record page. The mtr may be
				committed and restarted in this call. */
{
	ulint		root_page_no;
	ibool		drop = !space;
	ulint		zip_size;
	ulint		type;
	index_id_t	index_id;
	rec_t*		rec;
	const byte*	ptr;
	ulint		len;
	dict_index_t*	index;

	ut_ad(mutex_own(&(dict_sys->mutex)));
	ut_a(!dict_table_is_comp(dict_sys->sys_indexes));
	rec = btr_pcur_get_rec(pcur);
	ptr = rec_get_nth_field_old(rec, DICT_SYS_INDEXES_PAGE_NO_FIELD, &len);

	ut_ad(len == 4);

	root_page_no = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);

	if (drop && root_page_no == FIL_NULL) {
		/* The tree has been freed. */

		ut_print_timestamp(stderr);
		fprintf(stderr, "  InnoDB: Trying to TRUNCATE"
			" a missing index of table %s!\n", table->name);
		drop = FALSE;
	}

	ptr = rec_get_nth_field_old(rec,
				    DICT_SYS_INDEXES_SPACE_NO_FIELD, &len);

	ut_ad(len == 4);

	if (drop) {
		space = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);
	}

	zip_size = fil_space_get_zip_size(space);

	if (UNIV_UNLIKELY(zip_size == ULINT_UNDEFINED)) {
		/* It is a single table tablespace and the .ibd file is
		missing: do nothing */

		ut_print_timestamp(stderr);
		fprintf(stderr, "  InnoDB: Trying to TRUNCATE"
			" a missing .ibd file of table %s!\n", table->name);
		return(FIL_NULL);
	}

	ptr = rec_get_nth_field_old(rec,
				    DICT_SYS_INDEXES_TYPE_FIELD, &len);
	ut_ad(len == 4);
	type = mach_read_from_4(ptr);

	ptr = rec_get_nth_field_old(rec, 1, &len);
	ut_ad(len == 8);
	index_id = mach_read_from_8(ptr);

	if (!drop) {

		goto create;
	}

	/* We free all the pages but the root page first; this operation
	may span several mini-transactions */

	btr_free_but_not_root(space, zip_size, root_page_no);

	/* Then we free the root page in the same mini-transaction where
	we create the b-tree and write its new root page number to the
	appropriate field in the SYS_INDEXES record: this mini-transaction
	marks the B-tree totally truncated */

	btr_page_get(space, zip_size, root_page_no, RW_X_LATCH, mtr);

	btr_free_root(space, zip_size, root_page_no, mtr);
create:
	/* We will temporarily write FIL_NULL to the PAGE_NO field
	in SYS_INDEXES, so that the database will not get into an
	inconsistent state in case it crashes between the mtr_commit()
	below and the following mtr_commit() call. */
	page_rec_write_index_page_no(rec, DICT_SYS_INDEXES_PAGE_NO_FIELD,
				     FIL_NULL, mtr);

	/* We will need to commit the mini-transaction in order to avoid
	deadlocks in the btr_create() call, because otherwise we would
	be freeing and allocating pages in the same mini-transaction. */
	btr_pcur_store_position(pcur, mtr);
	mtr_commit(mtr);

	mtr_start(mtr);
	btr_pcur_restore_position(BTR_MODIFY_LEAF, pcur, mtr);

	/* Find the index corresponding to this SYS_INDEXES record. */
	for (index = UT_LIST_GET_FIRST(table->indexes);
	     index;
	     index = UT_LIST_GET_NEXT(indexes, index)) {
		if (index->id == index_id) {
			root_page_no = btr_create(type, space, zip_size,
						  index_id, index, mtr);
			index->page = (unsigned int) root_page_no;
			return(root_page_no);
		}
	}

	ut_print_timestamp(stderr);
	fprintf(stderr,
		"  InnoDB: Index %llu of table %s is missing\n"
		"InnoDB: from the data dictionary during TRUNCATE!\n",
		(ullint) index_id,
		table->name);

	return(FIL_NULL);
}

/*********************************************************************//**
Creates a table create graph.
@return	own: table create node */
UNIV_INTERN
tab_node_t*
tab_create_graph_create(
/*====================*/
	dict_table_t*	table,	/*!< in: table to create, built as a memory data
				structure */
	mem_heap_t*	heap)	/*!< in: heap where created */
{
	tab_node_t*	node;

	node = mem_heap_alloc(heap, sizeof(tab_node_t));

	node->common.type = QUE_NODE_CREATE_TABLE;

	node->table = table;

	node->state = TABLE_BUILD_TABLE_DEF;
	node->heap = mem_heap_create(256);

	node->tab_def = ins_node_create(INS_DIRECT, dict_sys->sys_tables,
					heap);
	node->tab_def->common.parent = node;

	node->col_def = ins_node_create(INS_DIRECT, dict_sys->sys_columns,
					heap);
	node->col_def->common.parent = node;

	node->commit_node = commit_node_create(heap);
	node->commit_node->common.parent = node;

	return(node);
}

/*********************************************************************//**
Creates an index create graph.
@return	own: index create node */
UNIV_INTERN
ind_node_t*
ind_create_graph_create(
/*====================*/
	dict_index_t*	index,	/*!< in: index to create, built as a memory data
				structure */
	mem_heap_t*	heap)	/*!< in: heap where created */
{
	ind_node_t*	node;

	node = mem_heap_alloc(heap, sizeof(ind_node_t));

	node->common.type = QUE_NODE_CREATE_INDEX;

	node->index = index;

	node->state = INDEX_BUILD_INDEX_DEF;
	node->page_no = FIL_NULL;
	node->heap = mem_heap_create(256);

	node->ind_def = ins_node_create(INS_DIRECT,
					dict_sys->sys_indexes, heap);
	node->ind_def->common.parent = node;

	node->field_def = ins_node_create(INS_DIRECT,
					  dict_sys->sys_fields, heap);
	node->field_def->common.parent = node;

	node->commit_node = commit_node_create(heap);
	node->commit_node->common.parent = node;

	return(node);
}

/***********************************************************//**
Creates a table. This is a high-level function used in SQL execution graphs.
@return	query thread to run next or NULL */
UNIV_INTERN
que_thr_t*
dict_create_table_step(
/*===================*/
	que_thr_t*	thr)	/*!< in: query thread */
{
	tab_node_t*	node;
	ulint		err	= DB_ERROR;
	trx_t*		trx;

	ut_ad(thr);
	ut_ad(mutex_own(&(dict_sys->mutex)));

	trx = thr_get_trx(thr);

	node = thr->run_node;

	ut_ad(que_node_get_type(node) == QUE_NODE_CREATE_TABLE);

	if (thr->prev_node == que_node_get_parent(node)) {
		node->state = TABLE_BUILD_TABLE_DEF;
	}

	if (node->state == TABLE_BUILD_TABLE_DEF) {

		/* DO THE CHECKS OF THE CONSISTENCY CONSTRAINTS HERE */

		err = dict_build_table_def_step(thr, node);

		if (err != DB_SUCCESS) {

			goto function_exit;
		}

		node->state = TABLE_BUILD_COL_DEF;
		node->col_no = 0;

		thr->run_node = node->tab_def;

		return(thr);
	}

	if (node->state == TABLE_BUILD_COL_DEF) {

		if (node->col_no < (node->table)->n_def) {

			err = dict_build_col_def_step(node);

			if (err != DB_SUCCESS) {

				goto function_exit;
			}

			node->col_no++;

			thr->run_node = node->col_def;

			return(thr);
		} else {
			node->state = TABLE_COMMIT_WORK;
		}
	}

	if (node->state == TABLE_COMMIT_WORK) {

		/* Table was correctly defined: do NOT commit the transaction
		(CREATE TABLE does NOT do an implicit commit of the current
		transaction) */

		node->state = TABLE_ADD_TO_CACHE;

		/* thr->run_node = node->commit_node;

		return(thr); */
	}

	if (node->state == TABLE_ADD_TO_CACHE) {

		dict_table_add_to_cache(node->table, node->heap);

		err = DB_SUCCESS;
	}

function_exit:
	trx->error_state = err;

	if (err == DB_SUCCESS) {
		/* Ok: do nothing */

	} else if (err == DB_LOCK_WAIT) {

		return(NULL);
	} else {
		/* SQL error detected */

		return(NULL);
	}

	thr->run_node = que_node_get_parent(node);

	return(thr);
}

/***********************************************************//**
Creates an index. This is a high-level function used in SQL execution
graphs.
@return	query thread to run next or NULL */
UNIV_INTERN
que_thr_t*
dict_create_index_step(
/*===================*/
	que_thr_t*	thr)	/*!< in: query thread */
{
	ind_node_t*	node;
	ulint		err	= DB_ERROR;
	trx_t*		trx;

	ut_ad(thr);
	ut_ad(mutex_own(&(dict_sys->mutex)));

	trx = thr_get_trx(thr);

	node = thr->run_node;

	ut_ad(que_node_get_type(node) == QUE_NODE_CREATE_INDEX);

	if (thr->prev_node == que_node_get_parent(node)) {
		node->state = INDEX_BUILD_INDEX_DEF;
	}

	if (node->state == INDEX_BUILD_INDEX_DEF) {
		/* DO THE CHECKS OF THE CONSISTENCY CONSTRAINTS HERE */
		err = dict_build_index_def_step(thr, node);

		if (err != DB_SUCCESS) {

			goto function_exit;
		}

		node->state = INDEX_BUILD_FIELD_DEF;
		node->field_no = 0;

		thr->run_node = node->ind_def;

		return(thr);
	}

	if (node->state == INDEX_BUILD_FIELD_DEF) {

		if (node->field_no < (node->index)->n_fields) {

			err = dict_build_field_def_step(node);

			if (err != DB_SUCCESS) {

				goto function_exit;
			}

			node->field_no++;

			thr->run_node = node->field_def;

			return(thr);
		} else {
			node->state = INDEX_ADD_TO_CACHE;
		}
	}

	if (node->state == INDEX_ADD_TO_CACHE) {

		index_id_t	index_id = node->index->id;

		err = dict_index_add_to_cache(
			node->table, node->index, FIL_NULL,
			trx_is_strict(trx)
			|| dict_table_get_format(node->table)
			>= DICT_TF_FORMAT_ZIP);

		node->index = dict_index_get_if_in_cache_low(index_id);
		ut_a(!node->index == (err != DB_SUCCESS));

		if (err != DB_SUCCESS) {

			goto function_exit;
		}

		node->state = INDEX_CREATE_INDEX_TREE;
	}

	if (node->state == INDEX_CREATE_INDEX_TREE) {

		err = dict_create_index_tree_step(node);

		if (err != DB_SUCCESS) {
			dict_index_remove_from_cache(node->table, node->index);
			node->index = NULL;

			goto function_exit;
		}

		node->index->page = node->page_no;
		node->state = INDEX_COMMIT_WORK;
	}

	if (node->state == INDEX_COMMIT_WORK) {

		/* Index was correctly defined: do NOT commit the transaction
		(CREATE INDEX does NOT currently do an implicit commit of
		the current transaction) */

		node->state = INDEX_CREATE_INDEX_TREE;

		/* thr->run_node = node->commit_node;

		return(thr); */
	}

function_exit:
	trx->error_state = err;

	if (err == DB_SUCCESS) {
		/* Ok: do nothing */

	} else if (err == DB_LOCK_WAIT) {

		return(NULL);
	} else {
		/* SQL error detected */

		return(NULL);
	}

	thr->run_node = que_node_get_parent(node);

	return(thr);
}

/****************************************************************//**
Creates the foreign key constraints system tables inside InnoDB
at database creation or database start if they are not found or are
not of the right form.
@return	DB_SUCCESS or error code */
UNIV_INTERN
ulint
dict_create_or_check_foreign_constraint_tables(void)
/*================================================*/
{
	dict_table_t*	table1;
	dict_table_t*	table2;
	ulint		error;
	trx_t*		trx;

	mutex_enter(&(dict_sys->mutex));

	table1 = dict_table_get_low("SYS_FOREIGN");
	table2 = dict_table_get_low("SYS_FOREIGN_COLS");

	if (table1 && table2
	    && UT_LIST_GET_LEN(table1->indexes) == 3
	    && UT_LIST_GET_LEN(table2->indexes) == 1) {

		/* Foreign constraint system tables have already been
		created, and they are ok */

		mutex_exit(&(dict_sys->mutex));

		return(DB_SUCCESS);
	}

	mutex_exit(&(dict_sys->mutex));

	trx = trx_allocate_for_mysql();

	trx->op_info = "creating foreign key sys tables";

	row_mysql_lock_data_dictionary(trx);

	if (table1) {
		fprintf(stderr,
			"InnoDB: dropping incompletely created"
			" SYS_FOREIGN table\n");
		row_drop_table_for_mysql("SYS_FOREIGN", trx, TRUE);
	}

	if (table2) {
		fprintf(stderr,
			"InnoDB: dropping incompletely created"
			" SYS_FOREIGN_COLS table\n");
		row_drop_table_for_mysql("SYS_FOREIGN_COLS", trx, TRUE);
	}

	fprintf(stderr,
		"InnoDB: Creating foreign key constraint system tables\n");

	/* NOTE: in dict_load_foreigns we use the fact that
	there are 2 secondary indexes on SYS_FOREIGN, and they
	are defined just like below */

	/* NOTE: when designing InnoDB's foreign key support in 2001, we made
	an error and made the table names and the foreign key id of type
	'CHAR' (internally, really a VARCHAR). We should have made the type
	VARBINARY, like in other InnoDB system tables, to get a clean
	design. */

	error = que_eval_sql(NULL,
			     "PROCEDURE CREATE_FOREIGN_SYS_TABLES_PROC () IS\n"
			     "BEGIN\n"
			     "CREATE TABLE\n"
			     "SYS_FOREIGN(ID CHAR, FOR_NAME CHAR,"
			     " REF_NAME CHAR, N_COLS INT);\n"
			     "CREATE UNIQUE CLUSTERED INDEX ID_IND"
			     " ON SYS_FOREIGN (ID);\n"
			     "CREATE INDEX FOR_IND"
			     " ON SYS_FOREIGN (FOR_NAME);\n"
			     "CREATE INDEX REF_IND"
			     " ON SYS_FOREIGN (REF_NAME);\n"
			     "CREATE TABLE\n"
			     "SYS_FOREIGN_COLS(ID CHAR, POS INT,"
			     " FOR_COL_NAME CHAR, REF_COL_NAME CHAR);\n"
			     "CREATE UNIQUE CLUSTERED INDEX ID_IND"
			     " ON SYS_FOREIGN_COLS (ID, POS);\n"
			     "END;\n"
			     , FALSE, trx);

	if (error != DB_SUCCESS) {
		fprintf(stderr, "InnoDB: error %lu in creation\n",
			(ulong) error);

		ut_a(error == DB_OUT_OF_FILE_SPACE
		     || error == DB_TOO_MANY_CONCURRENT_TRXS);

		fprintf(stderr,
			"InnoDB: creation failed\n"
			"InnoDB: tablespace is full\n"
			"InnoDB: dropping incompletely created"
			" SYS_FOREIGN tables\n");

		row_drop_table_for_mysql("SYS_FOREIGN", trx, TRUE);
		row_drop_table_for_mysql("SYS_FOREIGN_COLS", trx, TRUE);

		error = DB_MUST_GET_MORE_FILE_SPACE;
	}

	trx_commit_for_mysql(trx);

	row_mysql_unlock_data_dictionary(trx);

	trx_free_for_mysql(trx);

	if (error == DB_SUCCESS) {
		fprintf(stderr,
			"InnoDB: Foreign key constraint system tables"
			" created\n");
	}

	return(error);
}

/****************************************************************//**
Evaluate the given foreign key SQL statement.
@return	error code or DB_SUCCESS */
static
ulint
dict_foreign_eval_sql(
/*==================*/
	pars_info_t*	info,	/*!< in: info struct, or NULL */
	const char*	sql,	/*!< in: SQL string to evaluate */
	dict_table_t*	table,	/*!< in: table */
	dict_foreign_t*	foreign,/*!< in: foreign */
	trx_t*		trx)	/*!< in: transaction */
{
	ulint		error;
	FILE*		ef	= dict_foreign_err_file;

	error = que_eval_sql(info, sql, FALSE, trx);

	if (error == DB_DUPLICATE_KEY) {
		mutex_enter(&dict_foreign_err_mutex);
		rewind(ef);
		ut_print_timestamp(ef);
		fputs(" Error in foreign key constraint creation for table ",
		      ef);
		ut_print_name(ef, trx, TRUE, table->name);
		fputs(".\nA foreign key constraint of name ", ef);
		ut_print_name(ef, trx, TRUE, foreign->id);
		fputs("\nalready exists."
		      " (Note that internally InnoDB adds 'databasename'\n"
		      "in front of the user-defined constraint name.)\n"
		      "Note that InnoDB's FOREIGN KEY system tables store\n"
		      "constraint names as case-insensitive, with the\n"
		      "MySQL standard latin1_swedish_ci collation. If you\n"
		      "create tables or databases whose names differ only in\n"
		      "the character case, then collisions in constraint\n"
		      "names can occur. Workaround: name your constraints\n"
		      "explicitly with unique names.\n",
		      ef);

		mutex_exit(&dict_foreign_err_mutex);

		return(error);
	}

	if (error != DB_SUCCESS) {
		fprintf(stderr,
			"InnoDB: Foreign key constraint creation failed:\n"
			"InnoDB: internal error number %lu\n", (ulong) error);

		mutex_enter(&dict_foreign_err_mutex);
		ut_print_timestamp(ef);
		fputs(" Internal error in foreign key constraint creation"
		      " for table ", ef);
		ut_print_name(ef, trx, TRUE, table->name);
		fputs(".\n"
		      "See the MySQL .err log in the datadir"
		      " for more information.\n", ef);
		mutex_exit(&dict_foreign_err_mutex);

		return(error);
	}

	return(DB_SUCCESS);
}

/********************************************************************//**
Add a single foreign key field definition to the data dictionary tables in
the database.
@return	error code or DB_SUCCESS */
static
ulint
dict_create_add_foreign_field_to_dictionary(
/*========================================*/
	ulint		field_nr,	/*!< in: foreign field number */
	dict_table_t*	table,		/*!< in: table */
	dict_foreign_t*	foreign,	/*!< in: foreign */
	trx_t*		trx)		/*!< in: transaction */
{
	pars_info_t*	info = pars_info_create();

	pars_info_add_str_literal(info, "id", foreign->id);

	pars_info_add_int4_literal(info, "pos", field_nr);

	pars_info_add_str_literal(info, "for_col_name",
				  foreign->foreign_col_names[field_nr]);

	pars_info_add_str_literal(info, "ref_col_name",
				  foreign->referenced_col_names[field_nr]);

	return(dict_foreign_eval_sql(
		       info,
		       "PROCEDURE P () IS\n"
		       "BEGIN\n"
		       "INSERT INTO SYS_FOREIGN_COLS VALUES"
		       "(:id, :pos, :for_col_name, :ref_col_name);\n"
		       "END;\n",
		       table, foreign, trx));
}

/********************************************************************//**
Add a single foreign key definition to the data dictionary tables in the
database. We also generate names to constraints that were not named by the
user. A generated constraint has a name of the format
databasename/tablename_ibfk_NUMBER, where the numbers start from 1, and
are given locally for this table, that is, the number is not global, as in
the old format constraints < 4.0.18 it used to be.
@return	error code or DB_SUCCESS */
static
ulint
dict_create_add_foreign_to_dictionary(
/*==================================*/
	ulint*		id_nr,	/*!< in/out: number to use in id generation;
				incremented if used */
	dict_table_t*	table,	/*!< in: table */
	dict_foreign_t*	foreign,/*!< in: foreign */
	trx_t*		trx)	/*!< in: transaction */
{
	ulint		error;
	ulint		i;

	pars_info_t*	info = pars_info_create();

	if (foreign->id == NULL) {
		/* Generate a new constraint id */
		ulint	namelen	= strlen(table->name);
		char*	id	= mem_heap_alloc(foreign->heap, namelen + 20);
		/* no overflow if number < 1e13 */
		sprintf(id, "%s_ibfk_%lu", table->name, (ulong) (*id_nr)++);
		foreign->id = id;
	}

	pars_info_add_str_literal(info, "id", foreign->id);

	pars_info_add_str_literal(info, "for_name", table->name);

	pars_info_add_str_literal(info, "ref_name",
				  foreign->referenced_table_name);

	pars_info_add_int4_literal(info, "n_cols",
				   foreign->n_fields + (foreign->type << 24));

	error = dict_foreign_eval_sql(info,
				      "PROCEDURE P () IS\n"
				      "BEGIN\n"
				      "INSERT INTO SYS_FOREIGN VALUES"
				      "(:id, :for_name, :ref_name, :n_cols);\n"
				      "END;\n"
				      , table, foreign, trx);

	if (error != DB_SUCCESS) {

		return(error);
	}

	for (i = 0; i < foreign->n_fields; i++) {
		error = dict_create_add_foreign_field_to_dictionary(
			i, table, foreign, trx);

		if (error != DB_SUCCESS) {

			return(error);
		}
	}

	error = dict_foreign_eval_sql(NULL,
				      "PROCEDURE P () IS\n"
				      "BEGIN\n"
				      "COMMIT WORK;\n"
				      "END;\n"
				      , table, foreign, trx);

	return(error);
}

/********************************************************************//**
Adds foreign key definitions to data dictionary tables in the database.
@return	error code or DB_SUCCESS */
UNIV_INTERN
ulint
dict_create_add_foreigns_to_dictionary(
/*===================================*/
	ulint		start_id,/*!< in: if we are actually doing ALTER TABLE
				ADD CONSTRAINT, we want to generate constraint
				numbers which are bigger than in the table so
				far; we number the constraints from
				start_id + 1 up; start_id should be set to 0 if
				we are creating a new table, or if the table
				so far has no constraints for which the name
				was generated here */
	dict_table_t*	table,	/*!< in: table */
	trx_t*		trx)	/*!< in: transaction */
{
	dict_foreign_t*	foreign;
	ulint		number	= start_id + 1;
	ulint		error;

	ut_ad(mutex_own(&(dict_sys->mutex)));

	if (NULL == dict_table_get_low("SYS_FOREIGN")) {
		fprintf(stderr,
			"InnoDB: table SYS_FOREIGN not found"
			" in internal data dictionary\n");

		return(DB_ERROR);
	}

	for (foreign = UT_LIST_GET_FIRST(table->foreign_list);
	     foreign;
	     foreign = UT_LIST_GET_NEXT(foreign_list, foreign)) {

		error = dict_create_add_foreign_to_dictionary(&number, table,
							      foreign, trx);

		if (error != DB_SUCCESS) {

			return(error);
		}
	}

	return(DB_SUCCESS);
}