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fts5_main.c
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3064 lines (2779 loc) · 91.8 KB
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/*
** 2014 Jun 09
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
******************************************************************************
**
** This is an SQLite module implementing full-text search.
*/
#include "fts5Int.h"
/*
** This variable is set to false when running tests for which the on disk
** structures should not be corrupt. Otherwise, true. If it is false, extra
** assert() conditions in the fts5 code are activated - conditions that are
** only true if it is guaranteed that the fts5 database is not corrupt.
*/
#ifdef SQLITE_DEBUG
int sqlite3_fts5_may_be_corrupt = 1;
#endif
typedef struct Fts5Auxdata Fts5Auxdata;
typedef struct Fts5Auxiliary Fts5Auxiliary;
typedef struct Fts5Cursor Fts5Cursor;
typedef struct Fts5FullTable Fts5FullTable;
typedef struct Fts5Sorter Fts5Sorter;
typedef struct Fts5TokenizerModule Fts5TokenizerModule;
/*
** NOTES ON TRANSACTIONS:
**
** SQLite invokes the following virtual table methods as transactions are
** opened and closed by the user:
**
** xBegin(): Start of a new transaction.
** xSync(): Initial part of two-phase commit.
** xCommit(): Final part of two-phase commit.
** xRollback(): Rollback the transaction.
**
** Anything that is required as part of a commit that may fail is performed
** in the xSync() callback. Current versions of SQLite ignore any errors
** returned by xCommit().
**
** And as sub-transactions are opened/closed:
**
** xSavepoint(int S): Open savepoint S.
** xRelease(int S): Commit and close savepoint S.
** xRollbackTo(int S): Rollback to start of savepoint S.
**
** During a write-transaction the fts5_index.c module may cache some data
** in-memory. It is flushed to disk whenever xSync(), xRelease() or
** xSavepoint() is called. And discarded whenever xRollback() or xRollbackTo()
** is called.
**
** Additionally, if SQLITE_DEBUG is defined, an instance of the following
** structure is used to record the current transaction state. This information
** is not required, but it is used in the assert() statements executed by
** function fts5CheckTransactionState() (see below).
*/
struct Fts5TransactionState {
int eState; /* 0==closed, 1==open, 2==synced */
int iSavepoint; /* Number of open savepoints (0 -> none) */
};
/*
** A single object of this type is allocated when the FTS5 module is
** registered with a database handle. It is used to store pointers to
** all registered FTS5 extensions - tokenizers and auxiliary functions.
*/
struct Fts5Global {
fts5_api api; /* User visible part of object (see fts5.h) */
sqlite3 *db; /* Associated database connection */
i64 iNextId; /* Used to allocate unique cursor ids */
Fts5Auxiliary *pAux; /* First in list of all aux. functions */
Fts5TokenizerModule *pTok; /* First in list of all tokenizer modules */
Fts5TokenizerModule *pDfltTok; /* Default tokenizer module */
Fts5Cursor *pCsr; /* First in list of all open cursors */
};
/*
** Each auxiliary function registered with the FTS5 module is represented
** by an object of the following type. All such objects are stored as part
** of the Fts5Global.pAux list.
*/
struct Fts5Auxiliary {
Fts5Global *pGlobal; /* Global context for this function */
char *zFunc; /* Function name (nul-terminated) */
void *pUserData; /* User-data pointer */
fts5_extension_function xFunc; /* Callback function */
void (*xDestroy)(void*); /* Destructor function */
Fts5Auxiliary *pNext; /* Next registered auxiliary function */
};
/*
** Each tokenizer module registered with the FTS5 module is represented
** by an object of the following type. All such objects are stored as part
** of the Fts5Global.pTok list.
*/
struct Fts5TokenizerModule {
char *zName; /* Name of tokenizer */
void *pUserData; /* User pointer passed to xCreate() */
fts5_tokenizer x; /* Tokenizer functions */
void (*xDestroy)(void*); /* Destructor function */
Fts5TokenizerModule *pNext; /* Next registered tokenizer module */
};
struct Fts5FullTable {
Fts5Table p; /* Public class members from fts5Int.h */
Fts5Storage *pStorage; /* Document store */
Fts5Global *pGlobal; /* Global (connection wide) data */
Fts5Cursor *pSortCsr; /* Sort data from this cursor */
int iSavepoint; /* Successful xSavepoint()+1 */
int bInSavepoint;
#ifdef SQLITE_DEBUG
struct Fts5TransactionState ts;
#endif
};
struct Fts5MatchPhrase {
Fts5Buffer *pPoslist; /* Pointer to current poslist */
int nTerm; /* Size of phrase in terms */
};
/*
** pStmt:
** SELECT rowid, <fts> FROM <fts> ORDER BY +rank;
**
** aIdx[]:
** There is one entry in the aIdx[] array for each phrase in the query,
** the value of which is the offset within aPoslist[] following the last
** byte of the position list for the corresponding phrase.
*/
struct Fts5Sorter {
sqlite3_stmt *pStmt;
i64 iRowid; /* Current rowid */
const u8 *aPoslist; /* Position lists for current row */
int nIdx; /* Number of entries in aIdx[] */
int aIdx[1]; /* Offsets into aPoslist for current row */
};
/*
** Virtual-table cursor object.
**
** iSpecial:
** If this is a 'special' query (refer to function fts5SpecialMatch()),
** then this variable contains the result of the query.
**
** iFirstRowid, iLastRowid:
** These variables are only used for FTS5_PLAN_MATCH cursors. Assuming the
** cursor iterates in ascending order of rowids, iFirstRowid is the lower
** limit of rowids to return, and iLastRowid the upper. In other words, the
** WHERE clause in the user's query might have been:
**
** <tbl> MATCH <expr> AND rowid BETWEEN $iFirstRowid AND $iLastRowid
**
** If the cursor iterates in descending order of rowid, iFirstRowid
** is the upper limit (i.e. the "first" rowid visited) and iLastRowid
** the lower.
*/
struct Fts5Cursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
Fts5Cursor *pNext; /* Next cursor in Fts5Cursor.pCsr list */
int *aColumnSize; /* Values for xColumnSize() */
i64 iCsrId; /* Cursor id */
/* Zero from this point onwards on cursor reset */
int ePlan; /* FTS5_PLAN_XXX value */
int bDesc; /* True for "ORDER BY rowid DESC" queries */
i64 iFirstRowid; /* Return no rowids earlier than this */
i64 iLastRowid; /* Return no rowids later than this */
sqlite3_stmt *pStmt; /* Statement used to read %_content */
Fts5Expr *pExpr; /* Expression for MATCH queries */
Fts5Sorter *pSorter; /* Sorter for "ORDER BY rank" queries */
int csrflags; /* Mask of cursor flags (see below) */
i64 iSpecial; /* Result of special query */
/* "rank" function. Populated on demand from vtab.xColumn(). */
char *zRank; /* Custom rank function */
char *zRankArgs; /* Custom rank function args */
Fts5Auxiliary *pRank; /* Rank callback (or NULL) */
int nRankArg; /* Number of trailing arguments for rank() */
sqlite3_value **apRankArg; /* Array of trailing arguments */
sqlite3_stmt *pRankArgStmt; /* Origin of objects in apRankArg[] */
/* Auxiliary data storage */
Fts5Auxiliary *pAux; /* Currently executing extension function */
Fts5Auxdata *pAuxdata; /* First in linked list of saved aux-data */
/* Cache used by auxiliary functions xInst() and xInstCount() */
Fts5PoslistReader *aInstIter; /* One for each phrase */
int nInstAlloc; /* Size of aInst[] array (entries / 3) */
int nInstCount; /* Number of phrase instances */
int *aInst; /* 3 integers per phrase instance */
};
/*
** Bits that make up the "idxNum" parameter passed indirectly by
** xBestIndex() to xFilter().
*/
#define FTS5_BI_MATCH 0x0001 /* <tbl> MATCH ? */
#define FTS5_BI_RANK 0x0002 /* rank MATCH ? */
#define FTS5_BI_ROWID_EQ 0x0004 /* rowid == ? */
#define FTS5_BI_ROWID_LE 0x0008 /* rowid <= ? */
#define FTS5_BI_ROWID_GE 0x0010 /* rowid >= ? */
#define FTS5_BI_ORDER_RANK 0x0020
#define FTS5_BI_ORDER_ROWID 0x0040
#define FTS5_BI_ORDER_DESC 0x0080
/*
** Values for Fts5Cursor.csrflags
*/
#define FTS5CSR_EOF 0x01
#define FTS5CSR_REQUIRE_CONTENT 0x02
#define FTS5CSR_REQUIRE_DOCSIZE 0x04
#define FTS5CSR_REQUIRE_INST 0x08
#define FTS5CSR_FREE_ZRANK 0x10
#define FTS5CSR_REQUIRE_RESEEK 0x20
#define FTS5CSR_REQUIRE_POSLIST 0x40
#define BitFlagAllTest(x,y) (((x) & (y))==(y))
#define BitFlagTest(x,y) (((x) & (y))!=0)
/*
** Macros to Set(), Clear() and Test() cursor flags.
*/
#define CsrFlagSet(pCsr, flag) ((pCsr)->csrflags |= (flag))
#define CsrFlagClear(pCsr, flag) ((pCsr)->csrflags &= ~(flag))
#define CsrFlagTest(pCsr, flag) ((pCsr)->csrflags & (flag))
struct Fts5Auxdata {
Fts5Auxiliary *pAux; /* Extension to which this belongs */
void *pPtr; /* Pointer value */
void(*xDelete)(void*); /* Destructor */
Fts5Auxdata *pNext; /* Next object in linked list */
};
#ifdef SQLITE_DEBUG
#define FTS5_BEGIN 1
#define FTS5_SYNC 2
#define FTS5_COMMIT 3
#define FTS5_ROLLBACK 4
#define FTS5_SAVEPOINT 5
#define FTS5_RELEASE 6
#define FTS5_ROLLBACKTO 7
static void fts5CheckTransactionState(Fts5FullTable *p, int op, int iSavepoint){
switch( op ){
case FTS5_BEGIN:
assert( p->ts.eState==0 );
p->ts.eState = 1;
p->ts.iSavepoint = -1;
break;
case FTS5_SYNC:
assert( p->ts.eState==1 || p->ts.eState==2 );
p->ts.eState = 2;
break;
case FTS5_COMMIT:
assert( p->ts.eState==2 );
p->ts.eState = 0;
break;
case FTS5_ROLLBACK:
assert( p->ts.eState==1 || p->ts.eState==2 || p->ts.eState==0 );
p->ts.eState = 0;
break;
case FTS5_SAVEPOINT:
assert( p->ts.eState>=1 );
assert( iSavepoint>=0 );
assert( iSavepoint>=p->ts.iSavepoint );
p->ts.iSavepoint = iSavepoint;
break;
case FTS5_RELEASE:
assert( p->ts.eState>=1 );
assert( iSavepoint>=0 );
assert( iSavepoint<=p->ts.iSavepoint );
p->ts.iSavepoint = iSavepoint-1;
break;
case FTS5_ROLLBACKTO:
assert( p->ts.eState>=1 );
assert( iSavepoint>=-1 );
/* The following assert() can fail if another vtab strikes an error
** within an xSavepoint() call then SQLite calls xRollbackTo() - without
** having called xSavepoint() on this vtab. */
/* assert( iSavepoint<=p->ts.iSavepoint ); */
p->ts.iSavepoint = iSavepoint;
break;
}
}
#else
# define fts5CheckTransactionState(x,y,z)
#endif
/*
** Return true if pTab is a contentless table.
*/
static int fts5IsContentless(Fts5FullTable *pTab){
return pTab->p.pConfig->eContent==FTS5_CONTENT_NONE;
}
/*
** Delete a virtual table handle allocated by fts5InitVtab().
*/
static void fts5FreeVtab(Fts5FullTable *pTab){
if( pTab ){
sqlite3Fts5IndexClose(pTab->p.pIndex);
sqlite3Fts5StorageClose(pTab->pStorage);
sqlite3Fts5ConfigFree(pTab->p.pConfig);
sqlite3_free(pTab);
}
}
/*
** The xDisconnect() virtual table method.
*/
static int fts5DisconnectMethod(sqlite3_vtab *pVtab){
fts5FreeVtab((Fts5FullTable*)pVtab);
return SQLITE_OK;
}
/*
** The xDestroy() virtual table method.
*/
static int fts5DestroyMethod(sqlite3_vtab *pVtab){
Fts5Table *pTab = (Fts5Table*)pVtab;
int rc = sqlite3Fts5DropAll(pTab->pConfig);
if( rc==SQLITE_OK ){
fts5FreeVtab((Fts5FullTable*)pVtab);
}
return rc;
}
/*
** This function is the implementation of both the xConnect and xCreate
** methods of the FTS3 virtual table.
**
** The argv[] array contains the following:
**
** argv[0] -> module name ("fts5")
** argv[1] -> database name
** argv[2] -> table name
** argv[...] -> "column name" and other module argument fields.
*/
static int fts5InitVtab(
int bCreate, /* True for xCreate, false for xConnect */
sqlite3 *db, /* The SQLite database connection */
void *pAux, /* Hash table containing tokenizers */
int argc, /* Number of elements in argv array */
const char * const *argv, /* xCreate/xConnect argument array */
sqlite3_vtab **ppVTab, /* Write the resulting vtab structure here */
char **pzErr /* Write any error message here */
){
Fts5Global *pGlobal = (Fts5Global*)pAux;
const char **azConfig = (const char**)argv;
int rc = SQLITE_OK; /* Return code */
Fts5Config *pConfig = 0; /* Results of parsing argc/argv */
Fts5FullTable *pTab = 0; /* New virtual table object */
/* Allocate the new vtab object and parse the configuration */
pTab = (Fts5FullTable*)sqlite3Fts5MallocZero(&rc, sizeof(Fts5FullTable));
if( rc==SQLITE_OK ){
rc = sqlite3Fts5ConfigParse(pGlobal, db, argc, azConfig, &pConfig, pzErr);
assert( (rc==SQLITE_OK && *pzErr==0) || pConfig==0 );
}
if( rc==SQLITE_OK ){
pTab->p.pConfig = pConfig;
pTab->pGlobal = pGlobal;
}
/* Open the index sub-system */
if( rc==SQLITE_OK ){
rc = sqlite3Fts5IndexOpen(pConfig, bCreate, &pTab->p.pIndex, pzErr);
}
/* Open the storage sub-system */
if( rc==SQLITE_OK ){
rc = sqlite3Fts5StorageOpen(
pConfig, pTab->p.pIndex, bCreate, &pTab->pStorage, pzErr
);
}
/* Call sqlite3_declare_vtab() */
if( rc==SQLITE_OK ){
rc = sqlite3Fts5ConfigDeclareVtab(pConfig);
}
/* Load the initial configuration */
if( rc==SQLITE_OK ){
assert( pConfig->pzErrmsg==0 );
pConfig->pzErrmsg = pzErr;
rc = sqlite3Fts5IndexLoadConfig(pTab->p.pIndex);
sqlite3Fts5IndexRollback(pTab->p.pIndex);
pConfig->pzErrmsg = 0;
}
if( rc==SQLITE_OK && pConfig->eContent==FTS5_CONTENT_NORMAL ){
rc = sqlite3_vtab_config(db, SQLITE_VTAB_CONSTRAINT_SUPPORT, (int)1);
}
if( rc==SQLITE_OK ){
rc = sqlite3_vtab_config(db, SQLITE_VTAB_INNOCUOUS);
}
if( rc!=SQLITE_OK ){
fts5FreeVtab(pTab);
pTab = 0;
}else if( bCreate ){
fts5CheckTransactionState(pTab, FTS5_BEGIN, 0);
}
*ppVTab = (sqlite3_vtab*)pTab;
return rc;
}
/*
** The xConnect() and xCreate() methods for the virtual table. All the
** work is done in function fts5InitVtab().
*/
static int fts5ConnectMethod(
sqlite3 *db, /* Database connection */
void *pAux, /* Pointer to tokenizer hash table */
int argc, /* Number of elements in argv array */
const char * const *argv, /* xCreate/xConnect argument array */
sqlite3_vtab **ppVtab, /* OUT: New sqlite3_vtab object */
char **pzErr /* OUT: sqlite3_malloc'd error message */
){
return fts5InitVtab(0, db, pAux, argc, argv, ppVtab, pzErr);
}
static int fts5CreateMethod(
sqlite3 *db, /* Database connection */
void *pAux, /* Pointer to tokenizer hash table */
int argc, /* Number of elements in argv array */
const char * const *argv, /* xCreate/xConnect argument array */
sqlite3_vtab **ppVtab, /* OUT: New sqlite3_vtab object */
char **pzErr /* OUT: sqlite3_malloc'd error message */
){
return fts5InitVtab(1, db, pAux, argc, argv, ppVtab, pzErr);
}
/*
** The different query plans.
*/
#define FTS5_PLAN_MATCH 1 /* (<tbl> MATCH ?) */
#define FTS5_PLAN_SOURCE 2 /* A source cursor for SORTED_MATCH */
#define FTS5_PLAN_SPECIAL 3 /* An internal query */
#define FTS5_PLAN_SORTED_MATCH 4 /* (<tbl> MATCH ? ORDER BY rank) */
#define FTS5_PLAN_SCAN 5 /* No usable constraint */
#define FTS5_PLAN_ROWID 6 /* (rowid = ?) */
/*
** Set the SQLITE_INDEX_SCAN_UNIQUE flag in pIdxInfo->flags. Unless this
** extension is currently being used by a version of SQLite too old to
** support index-info flags. In that case this function is a no-op.
*/
static void fts5SetUniqueFlag(sqlite3_index_info *pIdxInfo){
#if SQLITE_VERSION_NUMBER>=3008012
#ifndef SQLITE_CORE
if( sqlite3_libversion_number()>=3008012 )
#endif
{
pIdxInfo->idxFlags |= SQLITE_INDEX_SCAN_UNIQUE;
}
#endif
}
static int fts5UsePatternMatch(
Fts5Config *pConfig,
struct sqlite3_index_constraint *p
){
assert( FTS5_PATTERN_GLOB==SQLITE_INDEX_CONSTRAINT_GLOB );
assert( FTS5_PATTERN_LIKE==SQLITE_INDEX_CONSTRAINT_LIKE );
if( pConfig->ePattern==FTS5_PATTERN_GLOB && p->op==FTS5_PATTERN_GLOB ){
return 1;
}
if( pConfig->ePattern==FTS5_PATTERN_LIKE
&& (p->op==FTS5_PATTERN_LIKE || p->op==FTS5_PATTERN_GLOB)
){
return 1;
}
return 0;
}
/*
** Implementation of the xBestIndex method for FTS5 tables. Within the
** WHERE constraint, it searches for the following:
**
** 1. A MATCH constraint against the table column.
** 2. A MATCH constraint against the "rank" column.
** 3. A MATCH constraint against some other column.
** 4. An == constraint against the rowid column.
** 5. A < or <= constraint against the rowid column.
** 6. A > or >= constraint against the rowid column.
**
** Within the ORDER BY, the following are supported:
**
** 5. ORDER BY rank [ASC|DESC]
** 6. ORDER BY rowid [ASC|DESC]
**
** Information for the xFilter call is passed via both the idxNum and
** idxStr variables. Specifically, idxNum is a bitmask of the following
** flags used to encode the ORDER BY clause:
**
** FTS5_BI_ORDER_RANK
** FTS5_BI_ORDER_ROWID
** FTS5_BI_ORDER_DESC
**
** idxStr is used to encode data from the WHERE clause. For each argument
** passed to the xFilter method, the following is appended to idxStr:
**
** Match against table column: "m"
** Match against rank column: "r"
** Match against other column: "M<column-number>"
** LIKE against other column: "L<column-number>"
** GLOB against other column: "G<column-number>"
** Equality constraint against the rowid: "="
** A < or <= against the rowid: "<"
** A > or >= against the rowid: ">"
**
** This function ensures that there is at most one "r" or "=". And that if
** there exists an "=" then there is no "<" or ">".
**
** Costs are assigned as follows:
**
** a) If an unusable MATCH operator is present in the WHERE clause, the
** cost is unconditionally set to 1e50 (a really big number).
**
** a) If a MATCH operator is present, the cost depends on the other
** constraints also present. As follows:
**
** * No other constraints: cost=1000.0
** * One rowid range constraint: cost=750.0
** * Both rowid range constraints: cost=500.0
** * An == rowid constraint: cost=100.0
**
** b) Otherwise, if there is no MATCH:
**
** * No other constraints: cost=1000000.0
** * One rowid range constraint: cost=750000.0
** * Both rowid range constraints: cost=250000.0
** * An == rowid constraint: cost=10.0
**
** Costs are not modified by the ORDER BY clause.
*/
static int fts5BestIndexMethod(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
Fts5Table *pTab = (Fts5Table*)pVTab;
Fts5Config *pConfig = pTab->pConfig;
const int nCol = pConfig->nCol;
int idxFlags = 0; /* Parameter passed through to xFilter() */
int i;
char *idxStr;
int iIdxStr = 0;
int iCons = 0;
int bSeenEq = 0;
int bSeenGt = 0;
int bSeenLt = 0;
int bSeenMatch = 0;
int bSeenRank = 0;
assert( SQLITE_INDEX_CONSTRAINT_EQ<SQLITE_INDEX_CONSTRAINT_MATCH );
assert( SQLITE_INDEX_CONSTRAINT_GT<SQLITE_INDEX_CONSTRAINT_MATCH );
assert( SQLITE_INDEX_CONSTRAINT_LE<SQLITE_INDEX_CONSTRAINT_MATCH );
assert( SQLITE_INDEX_CONSTRAINT_GE<SQLITE_INDEX_CONSTRAINT_MATCH );
assert( SQLITE_INDEX_CONSTRAINT_LE<SQLITE_INDEX_CONSTRAINT_MATCH );
if( pConfig->bLock ){
pTab->base.zErrMsg = sqlite3_mprintf(
"recursively defined fts5 content table"
);
return SQLITE_ERROR;
}
idxStr = (char*)sqlite3_malloc(pInfo->nConstraint * 8 + 1);
if( idxStr==0 ) return SQLITE_NOMEM;
pInfo->idxStr = idxStr;
pInfo->needToFreeIdxStr = 1;
for(i=0; i<pInfo->nConstraint; i++){
struct sqlite3_index_constraint *p = &pInfo->aConstraint[i];
int iCol = p->iColumn;
if( p->op==SQLITE_INDEX_CONSTRAINT_MATCH
|| (p->op==SQLITE_INDEX_CONSTRAINT_EQ && iCol>=nCol)
){
/* A MATCH operator or equivalent */
if( p->usable==0 || iCol<0 ){
/* As there exists an unusable MATCH constraint this is an
** unusable plan. Set a prohibitively high cost. */
pInfo->estimatedCost = 1e50;
assert( iIdxStr < pInfo->nConstraint*6 + 1 );
idxStr[iIdxStr] = 0;
return SQLITE_OK;
}else{
if( iCol==nCol+1 ){
if( bSeenRank ) continue;
idxStr[iIdxStr++] = 'r';
bSeenRank = 1;
}else if( iCol>=0 ){
bSeenMatch = 1;
idxStr[iIdxStr++] = 'M';
sqlite3_snprintf(6, &idxStr[iIdxStr], "%d", iCol);
idxStr += strlen(&idxStr[iIdxStr]);
assert( idxStr[iIdxStr]=='\0' );
}
pInfo->aConstraintUsage[i].argvIndex = ++iCons;
pInfo->aConstraintUsage[i].omit = 1;
}
}else if( p->usable ){
if( iCol>=0 && iCol<nCol && fts5UsePatternMatch(pConfig, p) ){
assert( p->op==FTS5_PATTERN_LIKE || p->op==FTS5_PATTERN_GLOB );
idxStr[iIdxStr++] = p->op==FTS5_PATTERN_LIKE ? 'L' : 'G';
sqlite3_snprintf(6, &idxStr[iIdxStr], "%d", iCol);
idxStr += strlen(&idxStr[iIdxStr]);
pInfo->aConstraintUsage[i].argvIndex = ++iCons;
assert( idxStr[iIdxStr]=='\0' );
}else if( bSeenEq==0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ && iCol<0 ){
idxStr[iIdxStr++] = '=';
bSeenEq = 1;
pInfo->aConstraintUsage[i].argvIndex = ++iCons;
}
}
}
if( bSeenEq==0 ){
for(i=0; i<pInfo->nConstraint; i++){
struct sqlite3_index_constraint *p = &pInfo->aConstraint[i];
if( p->iColumn<0 && p->usable ){
int op = p->op;
if( op==SQLITE_INDEX_CONSTRAINT_LT || op==SQLITE_INDEX_CONSTRAINT_LE ){
if( bSeenLt ) continue;
idxStr[iIdxStr++] = '<';
pInfo->aConstraintUsage[i].argvIndex = ++iCons;
bSeenLt = 1;
}else
if( op==SQLITE_INDEX_CONSTRAINT_GT || op==SQLITE_INDEX_CONSTRAINT_GE ){
if( bSeenGt ) continue;
idxStr[iIdxStr++] = '>';
pInfo->aConstraintUsage[i].argvIndex = ++iCons;
bSeenGt = 1;
}
}
}
}
idxStr[iIdxStr] = '\0';
/* Set idxFlags flags for the ORDER BY clause */
if( pInfo->nOrderBy==1 ){
int iSort = pInfo->aOrderBy[0].iColumn;
if( iSort==(pConfig->nCol+1) && bSeenMatch ){
idxFlags |= FTS5_BI_ORDER_RANK;
}else if( iSort==-1 ){
idxFlags |= FTS5_BI_ORDER_ROWID;
}
if( BitFlagTest(idxFlags, FTS5_BI_ORDER_RANK|FTS5_BI_ORDER_ROWID) ){
pInfo->orderByConsumed = 1;
if( pInfo->aOrderBy[0].desc ){
idxFlags |= FTS5_BI_ORDER_DESC;
}
}
}
/* Calculate the estimated cost based on the flags set in idxFlags. */
if( bSeenEq ){
pInfo->estimatedCost = bSeenMatch ? 100.0 : 10.0;
if( bSeenMatch==0 ) fts5SetUniqueFlag(pInfo);
}else if( bSeenLt && bSeenGt ){
pInfo->estimatedCost = bSeenMatch ? 500.0 : 250000.0;
}else if( bSeenLt || bSeenGt ){
pInfo->estimatedCost = bSeenMatch ? 750.0 : 750000.0;
}else{
pInfo->estimatedCost = bSeenMatch ? 1000.0 : 1000000.0;
}
pInfo->idxNum = idxFlags;
return SQLITE_OK;
}
static int fts5NewTransaction(Fts5FullTable *pTab){
Fts5Cursor *pCsr;
for(pCsr=pTab->pGlobal->pCsr; pCsr; pCsr=pCsr->pNext){
if( pCsr->base.pVtab==(sqlite3_vtab*)pTab ) return SQLITE_OK;
}
return sqlite3Fts5StorageReset(pTab->pStorage);
}
/*
** Implementation of xOpen method.
*/
static int fts5OpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
Fts5FullTable *pTab = (Fts5FullTable*)pVTab;
Fts5Config *pConfig = pTab->p.pConfig;
Fts5Cursor *pCsr = 0; /* New cursor object */
sqlite3_int64 nByte; /* Bytes of space to allocate */
int rc; /* Return code */
rc = fts5NewTransaction(pTab);
if( rc==SQLITE_OK ){
nByte = sizeof(Fts5Cursor) + pConfig->nCol * sizeof(int);
pCsr = (Fts5Cursor*)sqlite3_malloc64(nByte);
if( pCsr ){
Fts5Global *pGlobal = pTab->pGlobal;
memset(pCsr, 0, (size_t)nByte);
pCsr->aColumnSize = (int*)&pCsr[1];
pCsr->pNext = pGlobal->pCsr;
pGlobal->pCsr = pCsr;
pCsr->iCsrId = ++pGlobal->iNextId;
}else{
rc = SQLITE_NOMEM;
}
}
*ppCsr = (sqlite3_vtab_cursor*)pCsr;
return rc;
}
static int fts5StmtType(Fts5Cursor *pCsr){
if( pCsr->ePlan==FTS5_PLAN_SCAN ){
return (pCsr->bDesc) ? FTS5_STMT_SCAN_DESC : FTS5_STMT_SCAN_ASC;
}
return FTS5_STMT_LOOKUP;
}
/*
** This function is called after the cursor passed as the only argument
** is moved to point at a different row. It clears all cached data
** specific to the previous row stored by the cursor object.
*/
static void fts5CsrNewrow(Fts5Cursor *pCsr){
CsrFlagSet(pCsr,
FTS5CSR_REQUIRE_CONTENT
| FTS5CSR_REQUIRE_DOCSIZE
| FTS5CSR_REQUIRE_INST
| FTS5CSR_REQUIRE_POSLIST
);
}
static void fts5FreeCursorComponents(Fts5Cursor *pCsr){
Fts5FullTable *pTab = (Fts5FullTable*)(pCsr->base.pVtab);
Fts5Auxdata *pData;
Fts5Auxdata *pNext;
sqlite3_free(pCsr->aInstIter);
sqlite3_free(pCsr->aInst);
if( pCsr->pStmt ){
int eStmt = fts5StmtType(pCsr);
sqlite3Fts5StorageStmtRelease(pTab->pStorage, eStmt, pCsr->pStmt);
}
if( pCsr->pSorter ){
Fts5Sorter *pSorter = pCsr->pSorter;
sqlite3_finalize(pSorter->pStmt);
sqlite3_free(pSorter);
}
if( pCsr->ePlan!=FTS5_PLAN_SOURCE ){
sqlite3Fts5ExprFree(pCsr->pExpr);
}
for(pData=pCsr->pAuxdata; pData; pData=pNext){
pNext = pData->pNext;
if( pData->xDelete ) pData->xDelete(pData->pPtr);
sqlite3_free(pData);
}
sqlite3_finalize(pCsr->pRankArgStmt);
sqlite3_free(pCsr->apRankArg);
if( CsrFlagTest(pCsr, FTS5CSR_FREE_ZRANK) ){
sqlite3_free(pCsr->zRank);
sqlite3_free(pCsr->zRankArgs);
}
sqlite3Fts5IndexCloseReader(pTab->p.pIndex);
memset(&pCsr->ePlan, 0, sizeof(Fts5Cursor) - ((u8*)&pCsr->ePlan - (u8*)pCsr));
}
/*
** Close the cursor. For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts5CloseMethod(sqlite3_vtab_cursor *pCursor){
if( pCursor ){
Fts5FullTable *pTab = (Fts5FullTable*)(pCursor->pVtab);
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
Fts5Cursor **pp;
fts5FreeCursorComponents(pCsr);
/* Remove the cursor from the Fts5Global.pCsr list */
for(pp=&pTab->pGlobal->pCsr; (*pp)!=pCsr; pp=&(*pp)->pNext);
*pp = pCsr->pNext;
sqlite3_free(pCsr);
}
return SQLITE_OK;
}
static int fts5SorterNext(Fts5Cursor *pCsr){
Fts5Sorter *pSorter = pCsr->pSorter;
int rc;
rc = sqlite3_step(pSorter->pStmt);
if( rc==SQLITE_DONE ){
rc = SQLITE_OK;
CsrFlagSet(pCsr, FTS5CSR_EOF|FTS5CSR_REQUIRE_CONTENT);
}else if( rc==SQLITE_ROW ){
const u8 *a;
const u8 *aBlob;
int nBlob;
int i;
int iOff = 0;
rc = SQLITE_OK;
pSorter->iRowid = sqlite3_column_int64(pSorter->pStmt, 0);
nBlob = sqlite3_column_bytes(pSorter->pStmt, 1);
aBlob = a = sqlite3_column_blob(pSorter->pStmt, 1);
/* nBlob==0 in detail=none mode. */
if( nBlob>0 ){
for(i=0; i<(pSorter->nIdx-1); i++){
int iVal;
a += fts5GetVarint32(a, iVal);
iOff += iVal;
pSorter->aIdx[i] = iOff;
}
pSorter->aIdx[i] = &aBlob[nBlob] - a;
pSorter->aPoslist = a;
}
fts5CsrNewrow(pCsr);
}
return rc;
}
/*
** Set the FTS5CSR_REQUIRE_RESEEK flag on all FTS5_PLAN_MATCH cursors
** open on table pTab.
*/
static void fts5TripCursors(Fts5FullTable *pTab){
Fts5Cursor *pCsr;
for(pCsr=pTab->pGlobal->pCsr; pCsr; pCsr=pCsr->pNext){
if( pCsr->ePlan==FTS5_PLAN_MATCH
&& pCsr->base.pVtab==(sqlite3_vtab*)pTab
){
CsrFlagSet(pCsr, FTS5CSR_REQUIRE_RESEEK);
}
}
}
/*
** If the REQUIRE_RESEEK flag is set on the cursor passed as the first
** argument, close and reopen all Fts5IndexIter iterators that the cursor
** is using. Then attempt to move the cursor to a rowid equal to or laster
** (in the cursors sort order - ASC or DESC) than the current rowid.
**
** If the new rowid is not equal to the old, set output parameter *pbSkip
** to 1 before returning. Otherwise, leave it unchanged.
**
** Return SQLITE_OK if successful or if no reseek was required, or an
** error code if an error occurred.
*/
static int fts5CursorReseek(Fts5Cursor *pCsr, int *pbSkip){
int rc = SQLITE_OK;
assert( *pbSkip==0 );
if( CsrFlagTest(pCsr, FTS5CSR_REQUIRE_RESEEK) ){
Fts5FullTable *pTab = (Fts5FullTable*)(pCsr->base.pVtab);
int bDesc = pCsr->bDesc;
i64 iRowid = sqlite3Fts5ExprRowid(pCsr->pExpr);
rc = sqlite3Fts5ExprFirst(pCsr->pExpr, pTab->p.pIndex, iRowid, bDesc);
if( rc==SQLITE_OK && iRowid!=sqlite3Fts5ExprRowid(pCsr->pExpr) ){
*pbSkip = 1;
}
CsrFlagClear(pCsr, FTS5CSR_REQUIRE_RESEEK);
fts5CsrNewrow(pCsr);
if( sqlite3Fts5ExprEof(pCsr->pExpr) ){
CsrFlagSet(pCsr, FTS5CSR_EOF);
*pbSkip = 1;
}
}
return rc;
}
/*
** Advance the cursor to the next row in the table that matches the
** search criteria.
**
** Return SQLITE_OK if nothing goes wrong. SQLITE_OK is returned
** even if we reach end-of-file. The fts5EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts5NextMethod(sqlite3_vtab_cursor *pCursor){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int rc;
assert( (pCsr->ePlan<3)==
(pCsr->ePlan==FTS5_PLAN_MATCH || pCsr->ePlan==FTS5_PLAN_SOURCE)
);
assert( !CsrFlagTest(pCsr, FTS5CSR_EOF) );
if( pCsr->ePlan<3 ){
int bSkip = 0;
if( (rc = fts5CursorReseek(pCsr, &bSkip)) || bSkip ) return rc;
rc = sqlite3Fts5ExprNext(pCsr->pExpr, pCsr->iLastRowid);
CsrFlagSet(pCsr, sqlite3Fts5ExprEof(pCsr->pExpr));
fts5CsrNewrow(pCsr);
}else{
switch( pCsr->ePlan ){
case FTS5_PLAN_SPECIAL: {
CsrFlagSet(pCsr, FTS5CSR_EOF);
rc = SQLITE_OK;
break;
}
case FTS5_PLAN_SORTED_MATCH: {
rc = fts5SorterNext(pCsr);
break;
}
default: {
Fts5Config *pConfig = ((Fts5Table*)pCursor->pVtab)->pConfig;
pConfig->bLock++;
rc = sqlite3_step(pCsr->pStmt);
pConfig->bLock--;
if( rc!=SQLITE_ROW ){
CsrFlagSet(pCsr, FTS5CSR_EOF);
rc = sqlite3_reset(pCsr->pStmt);
if( rc!=SQLITE_OK ){
pCursor->pVtab->zErrMsg = sqlite3_mprintf(
"%s", sqlite3_errmsg(pConfig->db)
);
}
}else{
rc = SQLITE_OK;
}
break;
}
}
}
return rc;
}
static int fts5PrepareStatement(
sqlite3_stmt **ppStmt,
Fts5Config *pConfig,
const char *zFmt,
...
){
sqlite3_stmt *pRet = 0;
int rc;
char *zSql;
va_list ap;
va_start(ap, zFmt);
zSql = sqlite3_vmprintf(zFmt, ap);
if( zSql==0 ){
rc = SQLITE_NOMEM;
}else{
rc = sqlite3_prepare_v3(pConfig->db, zSql, -1,
SQLITE_PREPARE_PERSISTENT, &pRet, 0);
if( rc!=SQLITE_OK ){
*pConfig->pzErrmsg = sqlite3_mprintf("%s", sqlite3_errmsg(pConfig->db));
}
sqlite3_free(zSql);
}
va_end(ap);
*ppStmt = pRet;
return rc;
}
static int fts5CursorFirstSorted(
Fts5FullTable *pTab,
Fts5Cursor *pCsr,
int bDesc
){
Fts5Config *pConfig = pTab->p.pConfig;
Fts5Sorter *pSorter;
int nPhrase;
sqlite3_int64 nByte;
int rc;
const char *zRank = pCsr->zRank;
const char *zRankArgs = pCsr->zRankArgs;