mariadb/storage/innobase/include/fts0fts.h

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

Copyright (c) 2011, 2016, Oracle and/or its affiliates. All Rights Reserved.
Copyright (c) 2016, MariaDB Corporation. 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.,
51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA

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

/******************************************************************//**
@file include/fts0fts.h
Full text search header file

Created 2011/09/02 Sunny Bains
***********************************************************************/

#ifndef fts0fts_h
#define fts0fts_h

#include "univ.i"

#include "data0type.h"
#include "data0types.h"
#include "dict0types.h"
#include "hash0hash.h"
#include "mem0mem.h"
#include "rem0types.h"
#include "row0types.h"
#include "trx0types.h"
#include "ut0vec.h"
#include "ut0rbt.h"
#include "ut0wqueue.h"
#include "que0types.h"
#include "ft_global.h"

/** "NULL" value of a document id. */
#define FTS_NULL_DOC_ID			0

/** FTS hidden column that is used to map to and from the row */
#define FTS_DOC_ID_COL_NAME		"FTS_DOC_ID"

/** The name of the index created by FTS */
#define FTS_DOC_ID_INDEX_NAME		"FTS_DOC_ID_INDEX"

#define FTS_DOC_ID_INDEX_NAME_LEN	16

/** Doc ID is a 8 byte value */
#define FTS_DOC_ID_LEN			8

/** The number of fields to sort when we build FT index with
FIC. Three fields are sort: (word, doc_id, position) */
#define FTS_NUM_FIELDS_SORT		3

/** Maximum number of rows in a table, smaller than which, we will
optimize using a 4 byte Doc ID for FIC merge sort to reduce sort size */
#define MAX_DOC_ID_OPT_VAL		1073741824

/** Document id type. */
typedef ib_uint64_t doc_id_t;

/** doc_id_t printf format */
#define FTS_DOC_ID_FORMAT	IB_ID_FMT

/** Convert document id to the InnoDB (BIG ENDIAN) storage format. */
#define fts_write_doc_id(d, s)	mach_write_to_8(d, s)

/** Read a document id to internal format. */
#define fts_read_doc_id(s)	mach_read_from_8(s)

/** Bind the doc id to a variable */
#define fts_bind_doc_id(i, n, v) pars_info_bind_int8_literal(i, n, v)

/** Defines for FTS query mode, they have the same values as
those defined in mysql file ft_global.h */
#define FTS_NL		0
#define FTS_BOOL	1
#define FTS_SORTED	2
#define FTS_EXPAND	4
#define FTS_PROXIMITY	8
#define FTS_PHRASE	16
#define FTS_OPT_RANKING	32

#define FTS_INDEX_TABLE_IND_NAME	"FTS_INDEX_TABLE_IND"

/** Threshold where our optimize thread automatically kicks in */
#define FTS_OPTIMIZE_THRESHOLD		10000000

/** Threshold to avoid exhausting of doc ids. Consecutive doc id difference
should not exceed FTS_DOC_ID_MAX_STEP */
#define FTS_DOC_ID_MAX_STEP		65535

/** Variable specifying the FTS parallel sort degree */
extern ulong		fts_sort_pll_degree;

/** Variable specifying the number of word to optimize for each optimize table
call */
extern ulong		fts_num_word_optimize;

/** Variable specifying whether we do additional FTS diagnostic printout
in the log */
extern char		fts_enable_diag_print;

/** FTS rank type, which will be between 0 .. 1 inclusive */
typedef float 		fts_rank_t;

/** Type of a row during a transaction. FTS_NOTHING means the row can be
forgotten from the FTS system's POV, FTS_INVALID is an internal value used
to mark invalid states.

NOTE: Do not change the order or value of these, fts_trx_row_get_new_state
depends on them being exactly as they are. */
enum fts_row_state {
	FTS_INSERT = 0,
	FTS_MODIFY,
	FTS_DELETE,
	FTS_NOTHING,
	FTS_INVALID
};

/** The FTS table types. */
enum fts_table_type_t {
	FTS_INDEX_TABLE,		/*!< FTS auxiliary table that is
					specific to a particular FTS index
					on a table */

	FTS_COMMON_TABLE		/*!< FTS auxiliary table that is common
					for all FTS index on a table */
};

struct fts_doc_t;
struct fts_cache_t;
struct fts_token_t;
struct fts_doc_ids_t;
struct fts_index_cache_t;


/** Initialize the "fts_table" for internal query into FTS auxiliary
tables */
#define FTS_INIT_FTS_TABLE(fts_table, m_suffix, m_type, m_table)\
do {								\
	(fts_table)->suffix = m_suffix;				\
        (fts_table)->type = m_type;				\
        (fts_table)->table_id = m_table->id;			\
        (fts_table)->parent = m_table->name;			\
        (fts_table)->table = m_table;				\
} while (0);

#define FTS_INIT_INDEX_TABLE(fts_table, m_suffix, m_type, m_index)\
do {								\
	(fts_table)->suffix = m_suffix;				\
        (fts_table)->type = m_type;				\
        (fts_table)->table_id = m_index->table->id;		\
        (fts_table)->parent = m_index->table->name;		\
        (fts_table)->table = m_index->table;			\
        (fts_table)->index_id = m_index->id;			\
} while (0);

/** Information about changes in a single transaction affecting
the FTS system. */
struct fts_trx_t {
	trx_t*		trx;		/*!< InnoDB transaction */

	ib_vector_t*	savepoints;	/*!< Active savepoints, must have at
					least one element, the implied
					savepoint */
	ib_vector_t*	last_stmt;	/*!< last_stmt */

	mem_heap_t*	heap;		/*!< heap */
};

/** Information required for transaction savepoint handling. */
struct fts_savepoint_t {
	char*		name;		/*!< First entry is always NULL, the
					default instance. Otherwise the name
					of the savepoint */

	ib_rbt_t*	tables;		/*!< Modified FTS tables */
};

/** Information about changed rows in a transaction for a single table. */
struct fts_trx_table_t {
	dict_table_t*	table;		/*!< table */

	fts_trx_t*	fts_trx;	/*!< link to parent */

	ib_rbt_t*	rows;		/*!< rows changed; indexed by doc-id,
					cells are fts_trx_row_t* */

	fts_doc_ids_t*	added_doc_ids;	/*!< list of added doc ids (NULL until
					the first addition) */

					/*!< for adding doc ids */
	que_t*		docs_added_graph;
};

/** Information about one changed row in a transaction. */
struct fts_trx_row_t {
	doc_id_t	doc_id;		/*!< Id of the ins/upd/del document */

	fts_row_state	state;		/*!< state of the row */

	ib_vector_t*	fts_indexes;	/*!< The indexes that are affected */
};

/** List of document ids that were added during a transaction. This
list is passed on to a background 'Add' thread and OPTIMIZE, so it
needs its own memory heap. */
struct fts_doc_ids_t {
	ib_vector_t*	doc_ids;	/*!< document ids (each element is
					of type doc_id_t). */

	ib_alloc_t*	self_heap;	/*!< Allocator used to create an
					instance of this type and the
					doc_ids vector */
};

// FIXME: Get rid of this if possible.
/** Since MySQL's character set support for Unicode is woefully inadequate
(it supports basic operations like isalpha etc. only for 8-bit characters),
we have to implement our own. We use UTF-16 without surrogate processing
as our in-memory format. This typedef is a single such character. */
typedef unsigned short ib_uc_t;

/** An UTF-16 ro UTF-8 string. */
struct fts_string_t {
	byte*		f_str;		/*!< string, not necessary terminated in
					any way */
	ulint		f_len;		/*!< Length of the string in bytes */
	ulint		f_n_char;	/*!< Number of characters */
};

/** Query ranked doc ids. */
struct fts_ranking_t {
	doc_id_t	doc_id;		/*!< Document id */

	fts_rank_t	rank;		/*!< Rank is between 0 .. 1 */

	byte*		words;		/*!< this contains the words
					that were queried
					and found in this document */
	ulint		words_len;	/*!< words len */
};

/** Query result. */
struct fts_result_t {
	ib_rbt_node_t*	current;	/*!< Current element */

	ib_rbt_t*	rankings_by_id;	/*!< RB tree of type fts_ranking_t
					indexed by doc id */
	ib_rbt_t*	rankings_by_rank;/*!< RB tree of type fts_ranking_t
					indexed by rank */
};

/** This is used to generate the FTS auxiliary table name, we need the
table id and the index id to generate the column specific FTS auxiliary
table name. */
struct fts_table_t {
	const char*	parent;		/*!< Parent table name, this is
					required only for the database
					name */

	fts_table_type_t
			type;		/*!< The auxiliary table type */

	table_id_t	table_id;	/*!< The table id */

	index_id_t	index_id;	/*!< The index id */

	const char*	suffix;		/*!< The suffix of the fts auxiliary
					table name, can be NULL, not used
					everywhere (yet) */
	const dict_table_t*
			table;		/*!< Parent table */
	CHARSET_INFO*	charset;	/*!< charset info if it is for FTS
					index auxiliary table */
};

enum	fts_status {
	BG_THREAD_STOP = 1,	 	/*!< TRUE if the FTS background thread
					has finished reading the ADDED table,
					meaning more items can be added to
					the table. */

	BG_THREAD_READY = 2,		/*!< TRUE if the FTS background thread
					is ready */

	ADD_THREAD_STARTED = 4,		/*!< TRUE if the FTS add thread
					has started */

	ADDED_TABLE_SYNCED = 8,		/*!< TRUE if the ADDED table record is
					sync-ed after crash recovery */

	TABLE_DICT_LOCKED = 16		/*!< Set if the table has
					dict_sys->mutex */
};

typedef	enum fts_status	fts_status_t;

/** The state of the FTS sub system. */
struct fts_t {
					/*!< mutex protecting bg_threads* and
					fts_add_wq. */
	ib_mutex_t		bg_threads_mutex;

	ulint		bg_threads;	/*!< number of background threads
					accessing this table */

					/*!< TRUE if background threads running
					should stop themselves */
	ulint		fts_status;	/*!< Status bit regarding fts
					running state */

	ib_wqueue_t*	add_wq;		/*!< Work queue for scheduling jobs
					for the FTS 'Add' thread, or NULL
					if the thread has not yet been
					created. Each work item is a
					fts_trx_doc_ids_t*. */

	fts_cache_t*	cache;		/*!< FTS memory buffer for this table,
					or NULL if the table has no FTS
					index. */

	ulint		doc_col;	/*!< FTS doc id hidden column number
					in the CLUSTERED index. */

	ib_vector_t*	indexes;	/*!< Vector of FTS indexes, this is
					mainly for caching purposes. */
	mem_heap_t*	fts_heap;	/*!< heap for fts_t allocation */
};

struct fts_stopword_t;

/** status bits for fts_stopword_t status field. */
#define STOPWORD_NOT_INIT               0x1
#define STOPWORD_OFF                    0x2
#define STOPWORD_FROM_DEFAULT           0x4
#define STOPWORD_USER_TABLE             0x8

extern const char*	fts_default_stopword[];

/** Variable specifying the maximum FTS cache size for each table */
extern ulong		fts_max_cache_size;

/** Variable specifying the total memory allocated for FTS cache */
extern ulong		fts_max_total_cache_size;

/** Variable specifying the FTS result cache limit for each query */
extern ulong		fts_result_cache_limit;

/** Variable specifying the maximum FTS max token size */
extern ulong		fts_max_token_size;

/** Variable specifying the minimum FTS max token size */
extern ulong		fts_min_token_size;

/** Whether the total memory used for FTS cache is exhausted, and we will
need a sync to free some memory */
extern bool		fts_need_sync;

/** Maximum possible Fulltext word length in bytes (assuming mbmaxlen=4) */
#define FTS_MAX_WORD_LEN		(HA_FT_MAXCHARLEN * 4)

/** Maximum possible Fulltext word length (in characters) */
#define FTS_MAX_WORD_LEN_IN_CHAR	HA_FT_MAXCHARLEN

/** Variable specifying the table that has Fulltext index to display its
content through information schema table */
extern char*		fts_internal_tbl_name;
extern char*		fts_internal_tbl_name2;

#define	fts_que_graph_free(graph)			\
do {							\
	mutex_enter(&dict_sys->mutex);			\
	que_graph_free(graph);				\
	mutex_exit(&dict_sys->mutex);			\
} while (0)

/******************************************************************//**
Create a FTS cache. */
UNIV_INTERN
fts_cache_t*
fts_cache_create(
/*=============*/
	dict_table_t*	table);			/*!< table owns the FTS cache */

/******************************************************************//**
Create a FTS index cache.
@return Index Cache */
UNIV_INTERN
fts_index_cache_t*
fts_cache_index_cache_create(
/*=========================*/
	dict_table_t*	table,			/*!< in: table with FTS index */
	dict_index_t*	index);			/*!< in: FTS index */

/******************************************************************//**
Get the next available document id. This function creates a new
transaction to generate the document id.
@return DB_SUCCESS if OK */
UNIV_INTERN
dberr_t
fts_get_next_doc_id(
/*================*/
	const dict_table_t*	table,	/*!< in: table */
	doc_id_t*		doc_id)	/*!< out: new document id */
	MY_ATTRIBUTE((nonnull));
/*********************************************************************//**
Update the next and last Doc ID in the CONFIG table to be the input
"doc_id" value (+ 1). We would do so after each FTS index build or
table truncate */
UNIV_INTERN
void
fts_update_next_doc_id(
/*===================*/
	trx_t*			trx,		/*!< in/out: transaction */
	const dict_table_t*	table,		/*!< in: table */
	const char*		table_name,	/*!< in: table name, or NULL */
	doc_id_t		doc_id)		/*!< in: DOC ID to set */
	MY_ATTRIBUTE((nonnull(2)));

/******************************************************************//**
Create a new document id .
@return DB_SUCCESS if all went well else error */
UNIV_INTERN
dberr_t
fts_create_doc_id(
/*==============*/
	dict_table_t*	table,			/*!< in: row is of this
						table. */
	dtuple_t*	row,			/*!< in/out: add doc id
						value to this row. This is the
						current row that is being
						inserted. */
	mem_heap_t*	heap)			/*!< in: heap */
	MY_ATTRIBUTE((nonnull));
/******************************************************************//**
Create a new fts_doc_ids_t.
@return new fts_doc_ids_t. */
UNIV_INTERN
fts_doc_ids_t*
fts_doc_ids_create(void);
/*=====================*/

/******************************************************************//**
Free a fts_doc_ids_t. */
UNIV_INTERN
void
fts_doc_ids_free(
/*=============*/
	fts_doc_ids_t*	doc_ids);		/*!< in: doc_ids to free */

/******************************************************************//**
Notify the FTS system about an operation on an FTS-indexed table. */
UNIV_INTERN
void
fts_trx_add_op(
/*===========*/
	trx_t*		trx,			/*!< in: InnoDB transaction */
	dict_table_t*	table,			/*!< in: table */
	doc_id_t	doc_id,			/*!< in: doc id */
	fts_row_state	state,			/*!< in: state of the row */
	ib_vector_t*	fts_indexes)		/*!< in: FTS indexes affected
						(NULL=all) */
	MY_ATTRIBUTE((nonnull(1,2)));

/******************************************************************//**
Free an FTS trx. */
UNIV_INTERN
void
fts_trx_free(
/*=========*/
	fts_trx_t*	fts_trx);		/*!< in, own: FTS trx */

/******************************************************************//**
Creates the common ancillary tables needed for supporting an FTS index
on the given table. row_mysql_lock_data_dictionary must have been
called before this.
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_create_common_tables(
/*=====================*/
	trx_t*		trx,			/*!< in: transaction handle */
	const dict_table_t*
			table,			/*!< in: table with one FTS
						index */
	const char*	name,			/*!< in: table name */
	bool		skip_doc_id_index)	/*!< in: Skip index on doc id */
	MY_ATTRIBUTE((nonnull, warn_unused_result));
/******************************************************************//**
Wrapper function of fts_create_index_tables_low(), create auxiliary
tables for an FTS index
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_create_index_tables(
/*====================*/
	trx_t*			trx,		/*!< in: transaction handle */
	const dict_index_t*	index)		/*!< in: the FTS index
						instance */
	MY_ATTRIBUTE((nonnull, warn_unused_result));
/******************************************************************//**
Creates the column specific ancillary tables needed for supporting an
FTS index on the given table. row_mysql_lock_data_dictionary must have
been called before this.
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_create_index_tables_low(
/*========================*/
	trx_t*		trx,			/*!< in: transaction handle */
	const dict_index_t*
			index,			/*!< in: the FTS index
						instance */
	const char*	table_name,		/*!< in: the table name */
	table_id_t	table_id)		/*!< in: the table id */
	MY_ATTRIBUTE((nonnull, warn_unused_result));
/******************************************************************//**
Add the FTS document id hidden column. */
UNIV_INTERN
void
fts_add_doc_id_column(
/*==================*/
	dict_table_t*	table,	/*!< in/out: Table with FTS index */
	mem_heap_t*	heap)	/*!< in: temporary memory heap, or NULL */
	MY_ATTRIBUTE((nonnull(1)));

/*********************************************************************//**
Drops the ancillary tables needed for supporting an FTS index on the
given table. row_mysql_lock_data_dictionary must have been called before
this.
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_drop_tables(
/*============*/
	trx_t*		trx,			/*!< in: transaction */
	dict_table_t*	table)			/*!< in: table has the FTS
						index */
	MY_ATTRIBUTE((nonnull));
/******************************************************************//**
The given transaction is about to be committed; do whatever is necessary
from the FTS system's POV.
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_commit(
/*=======*/
	trx_t*		trx)			/*!< in: transaction */
	MY_ATTRIBUTE((nonnull, warn_unused_result));

/*******************************************************************//**
FTS Query entry point.
@return DB_SUCCESS if successful otherwise error code */
UNIV_INTERN
dberr_t
fts_query(
/*======*/
	trx_t*		trx,			/*!< in: transaction */
	dict_index_t*	index,			/*!< in: FTS index to search */
	uint		flags,			/*!< in: FTS search mode */
	const byte*	query,			/*!< in: FTS query */
	ulint		query_len,		/*!< in: FTS query string len
						in bytes */
	fts_result_t**	result)			/*!< out: query result, to be
						freed by the caller.*/
	MY_ATTRIBUTE((nonnull, warn_unused_result));

/******************************************************************//**
Retrieve the FTS Relevance Ranking result for doc with doc_id
@return the relevance ranking value. */
UNIV_INTERN
float
fts_retrieve_ranking(
/*=================*/
	fts_result_t*	result,			/*!< in: FTS result structure */
	doc_id_t	doc_id);		/*!< in: the interested document
						doc_id */

/******************************************************************//**
FTS Query sort result, returned by fts_query() on fts_ranking_t::rank. */
UNIV_INTERN
void
fts_query_sort_result_on_rank(
/*==========================*/
	fts_result_t*	result);		/*!< out: result instance
						to sort.*/

/******************************************************************//**
FTS Query free result, returned by fts_query(). */
UNIV_INTERN
void
fts_query_free_result(
/*==================*/
	fts_result_t*	result);		/*!< in: result instance
						to free.*/

/******************************************************************//**
Extract the doc id from the FTS hidden column. */
UNIV_INTERN
doc_id_t
fts_get_doc_id_from_row(
/*====================*/
	dict_table_t*	table,			/*!< in: table */
	dtuple_t*	row);			/*!< in: row whose FTS doc id we
						want to extract.*/

/******************************************************************//**
Extract the doc id from the FTS hidden column. */
UNIV_INTERN
doc_id_t
fts_get_doc_id_from_rec(
/*====================*/
	dict_table_t*	table,			/*!< in: table */
	const rec_t*	rec,			/*!< in: rec */
	mem_heap_t*	heap);			/*!< in: heap */

/******************************************************************//**
Update the query graph with a new document id.
@return Doc ID used */
UNIV_INTERN
doc_id_t
fts_update_doc_id(
/*==============*/
	dict_table_t*	table,			/*!< in: table */
	upd_field_t*	ufield,			/*!< out: update node */
	doc_id_t*	next_doc_id);		/*!< out: buffer for writing */

/******************************************************************//**
FTS initialize. */
UNIV_INTERN
void
fts_startup(void);
/*==============*/

/******************************************************************//**
Signal FTS threads to initiate shutdown. */
UNIV_INTERN
void
fts_start_shutdown(
/*===============*/
	dict_table_t*	table,			/*!< in: table with FTS
						indexes */
	fts_t*		fts);			/*!< in: fts instance to
						shutdown */

/******************************************************************//**
Wait for FTS threads to shutdown. */
UNIV_INTERN
void
fts_shutdown(
/*=========*/
	dict_table_t*	table,			/*!< in: table with FTS
						indexes */
	fts_t*		fts);			/*!< in: fts instance to
						shutdown */

/******************************************************************//**
Create an instance of fts_t.
@return instance of fts_t */
UNIV_INTERN
fts_t*
fts_create(
/*=======*/
	dict_table_t*	table);			/*!< out: table with FTS
						indexes */

/**********************************************************************//**
Free the FTS resources. */
UNIV_INTERN
void
fts_free(
/*=====*/
	dict_table_t*   table);			/*!< in/out: table with
						FTS indexes */

/*********************************************************************//**
Run OPTIMIZE on the given table.
@return DB_SUCCESS if all OK */
UNIV_INTERN
dberr_t
fts_optimize_table(
/*===============*/
	dict_table_t*	table)			/*!< in: table to optimiza */
	MY_ATTRIBUTE((nonnull));

/**********************************************************************//**
Startup the optimize thread and create the work queue. */
UNIV_INTERN
void
fts_optimize_init(void);
/*====================*/

/**********************************************************************//**
Check whether the work queue is initialized.
@return TRUE if optimze queue is initialized. */
UNIV_INTERN
ibool
fts_optimize_is_init(void);
/*======================*/

/****************************************************************//**
Drops index ancillary tables for a FTS index
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_drop_index_tables(
/*==================*/
	trx_t*		trx,			/*!< in: transaction */
	dict_index_t*	index)			/*!< in: Index to drop */
	MY_ATTRIBUTE((nonnull, warn_unused_result));

/******************************************************************//**
Remove the table from the OPTIMIZER's list. We do wait for
acknowledgement from the consumer of the message. */
UNIV_INTERN
void
fts_optimize_remove_table(
/*======================*/
	dict_table_t*	table);			/*!< in: table to remove */

/** Send sync fts cache for the table.
@param[in]	table	table to sync */
UNIV_INTERN
void
fts_optimize_request_sync_table(
	dict_table_t*	table);

/**********************************************************************//**
Signal the optimize thread to prepare for shutdown. */
UNIV_INTERN
void
fts_optimize_start_shutdown(void);
/*==============================*/

/**********************************************************************//**
Inform optimize to clean up. */
UNIV_INTERN
void
fts_optimize_end(void);
/*===================*/

/**********************************************************************//**
Take a FTS savepoint. */
UNIV_INTERN
void
fts_savepoint_take(
/*===============*/
	trx_t*		trx,			/*!< in: transaction */
	fts_trx_t*	fts_trx,		/*!< in: fts transaction */
	const char*	name)			/*!< in: savepoint name */
	MY_ATTRIBUTE((nonnull));
/**********************************************************************//**
Refresh last statement savepoint. */
UNIV_INTERN
void
fts_savepoint_laststmt_refresh(
/*===========================*/
	trx_t*		trx)			/*!< in: transaction */
	MY_ATTRIBUTE((nonnull));
/**********************************************************************//**
Release the savepoint data identified by  name. */
UNIV_INTERN
void
fts_savepoint_release(
/*==================*/
	trx_t*		trx,			/*!< in: transaction */
	const char*	name);			/*!< in: savepoint name */

/**********************************************************************//**
Free the FTS cache. */
UNIV_INTERN
void
fts_cache_destroy(
/*==============*/
	fts_cache_t*	cache);			/*!< in: cache*/

/** Clear cache.
@param[in,out]	cache	fts cache */
UNIV_INTERN
void
fts_cache_clear(
	fts_cache_t*	cache);

/*********************************************************************//**
Initialize things in cache. */
UNIV_INTERN
void
fts_cache_init(
/*===========*/
	fts_cache_t*	cache);			/*!< in: cache */

/*********************************************************************//**
Rollback to and including savepoint indentified by name. */
UNIV_INTERN
void
fts_savepoint_rollback(
/*===================*/
	trx_t*		trx,			/*!< in: transaction */
	const char*	name);			/*!< in: savepoint name */

/*********************************************************************//**
Rollback to and including savepoint indentified by name. */
UNIV_INTERN
void
fts_savepoint_rollback_last_stmt(
/*=============================*/
	trx_t*		trx);			/*!< in: transaction */

/***********************************************************************//**
Drop all orphaned FTS auxiliary tables, those that don't have a parent
table or FTS index defined on them. */
UNIV_INTERN
void
fts_drop_orphaned_tables(void);
/*==========================*/

/* Get parent table name if it's a fts aux table
@param[in]	aux_table_name	aux table name
@param[in]	aux_table_len	aux table length
@return parent table name, or NULL */
char*
fts_get_parent_table_name(
	const char*	aux_table_name,
	ulint		aux_table_len);

/******************************************************************//**
Since we do a horizontal split on the index table, we need to drop
all the split tables.
@return DB_SUCCESS or error code */
UNIV_INTERN
dberr_t
fts_drop_index_split_tables(
/*========================*/
	trx_t*		trx,			/*!< in: transaction */
	dict_index_t*	index)			/*!< in: fts instance */
	MY_ATTRIBUTE((nonnull, warn_unused_result));

/** Run SYNC on the table, i.e., write out data from the cache to the
FTS auxiliary INDEX table and clear the cache at the end.
@param[in,out]	table		fts table
@param[in]	unlock_cache	whether unlock cache when write node
@param[in]	wait		whether wait for existing sync to finish
@param[in]      has_dict        whether has dict operation lock
@return DB_SUCCESS on success, error code on failure. */
UNIV_INTERN
dberr_t
fts_sync_table(
	dict_table_t*	table,
	bool		unlock_cache,
	bool		wait,
	bool		has_dict);

/****************************************************************//**
Free the query graph but check whether dict_sys->mutex is already
held */
UNIV_INTERN
void
fts_que_graph_free_check_lock(
/*==========================*/
	fts_table_t*		fts_table,	/*!< in: FTS table */
	const fts_index_cache_t*index_cache,	/*!< in: FTS index cache */
	que_t*			graph);		/*!< in: query graph */

/****************************************************************//**
Create an FTS index cache. */
UNIV_INTERN
CHARSET_INFO*
fts_index_get_charset(
/*==================*/
	dict_index_t*		index);		/*!< in: FTS index */

/*********************************************************************//**
Get the initial Doc ID by consulting the CONFIG table
@return initial Doc ID */
UNIV_INTERN
doc_id_t
fts_init_doc_id(
/*============*/
	const dict_table_t*		table);	/*!< in: table */

/******************************************************************//**
compare two character string according to their charset. */
extern
int
innobase_fts_text_cmp(
/*==================*/
	const void*	cs,			/*!< in: Character set */
	const void*	p1,			/*!< in: key */
	const void*	p2);			/*!< in: node */

/******************************************************************//**
Makes all characters in a string lower case. */
extern
size_t
innobase_fts_casedn_str(
/*====================*/
        CHARSET_INFO*	cs,			/*!< in: Character set */
	char*		src,			/*!< in: string to put in
						lower case */
	size_t		src_len,		/*!< in: input string length */
	char*		dst,			/*!< in: buffer for result
						string */
	size_t		dst_len);		/*!< in: buffer size */


/******************************************************************//**
compare two character string according to their charset. */
extern
int
innobase_fts_text_cmp_prefix(
/*=========================*/
	const void*	cs,			/*!< in: Character set */
	const void*	p1,			/*!< in: key */
	const void*	p2);			/*!< in: node */

/*************************************************************//**
Get the next token from the given string and store it in *token. */
extern
ulint
innobase_mysql_fts_get_token(
/*=========================*/
	CHARSET_INFO*	charset,		/*!< in: Character set */
	const byte*	start,			/*!< in: start of text */
	const byte*	end,			/*!< in: one character past
						end of text */
	fts_string_t*	token,			/*!< out: token's text */
	ulint*		offset);		/*!< out: offset to token,
						measured as characters from
						'start' */

/*********************************************************************//**
Fetch COUNT(*) from specified table.
@return the number of rows in the table */
UNIV_INTERN
ulint
fts_get_rows_count(
/*===============*/
	fts_table_t*	fts_table);		/*!< in: fts table to read */

/*************************************************************//**
Get maximum Doc ID in a table if index "FTS_DOC_ID_INDEX" exists
@return max Doc ID or 0 if index "FTS_DOC_ID_INDEX" does not exist */
UNIV_INTERN
doc_id_t
fts_get_max_doc_id(
/*===============*/
	dict_table_t*	table);			/*!< in: user table */

/******************************************************************//**
Check whether user supplied stopword table exists and is of
the right format.
@return the stopword column charset if qualifies */
UNIV_INTERN
CHARSET_INFO*
fts_valid_stopword_table(
/*=====================*/
	const char*	stopword_table_name);	/*!< in: Stopword table
						name */
/****************************************************************//**
This function loads specified stopword into FTS cache
@return TRUE if success */
UNIV_INTERN
ibool
fts_load_stopword(
/*==============*/
	const dict_table_t*
			table,			/*!< in: Table with FTS */
	trx_t*		trx,			/*!< in: Transaction */
	const char*	global_stopword_table,	/*!< in: Global stopword table
						name */
	const char*	session_stopword_table,	/*!< in: Session stopword table
						name */
	ibool		stopword_is_on,		/*!< in: Whether stopword
						option is turned on/off */
	ibool		reload);		/*!< in: Whether it is during
						reload of FTS table */

/****************************************************************//**
Create the vector of fts_get_doc_t instances.
@return vector of fts_get_doc_t instances */
UNIV_INTERN
ib_vector_t*
fts_get_docs_create(
/*================*/
	fts_cache_t*	cache);			/*!< in: fts cache */

/****************************************************************//**
Read the rows from the FTS index
@return DB_SUCCESS if OK */
UNIV_INTERN
dberr_t
fts_table_fetch_doc_ids(
/*====================*/
	trx_t*		trx,			/*!< in: transaction */
	fts_table_t*	fts_table,		/*!< in: aux table */
	fts_doc_ids_t*	doc_ids);		/*!< in: For collecting
						doc ids */
/****************************************************************//**
This function brings FTS index in sync when FTS index is first
used. There are documents that have not yet sync-ed to auxiliary
tables from last server abnormally shutdown, we will need to bring
such document into FTS cache before any further operations
@return TRUE if all OK */
UNIV_INTERN
ibool
fts_init_index(
/*===========*/
	dict_table_t*	table,			/*!< in: Table with FTS */
	ibool		has_cache_lock);	/*!< in: Whether we already
						have cache lock */
/*******************************************************************//**
Add a newly create index in FTS cache */
UNIV_INTERN
void
fts_add_index(
/*==========*/
	dict_index_t*	index,			/*!< FTS index to be added */
	dict_table_t*	table);			/*!< table */

/*******************************************************************//**
Drop auxiliary tables related to an FTS index
@return DB_SUCCESS or error number */
UNIV_INTERN
dberr_t
fts_drop_index(
/*===========*/
	dict_table_t*	table,	/*!< in: Table where indexes are dropped */
	dict_index_t*	index,	/*!< in: Index to be dropped */
	trx_t*		trx)	/*!< in: Transaction for the drop */
	MY_ATTRIBUTE((nonnull));

/****************************************************************//**
Rename auxiliary tables for all fts index for a table
@return DB_SUCCESS or error code */

dberr_t
fts_rename_aux_tables(
/*==================*/
	dict_table_t*	table,		/*!< in: user Table */
	const char*	new_name,	/*!< in: new table name */
	trx_t*		trx);		/*!< in: transaction */

/*******************************************************************//**
Check indexes in the fts->indexes is also present in index cache and
table->indexes list
@return TRUE if all indexes match */
UNIV_INTERN
ibool
fts_check_cached_index(
/*===================*/
	dict_table_t*	table);  /*!< in: Table where indexes are dropped */
#endif /*!< fts0fts.h */