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mirror of https://github.com/tursodatabase/libsql.git synced 2024-12-15 07:29:41 +00:00
2023-11-15 14:46:34 +01:00

1025 lines
33 KiB
C

/*
** This file implements an eponymous, read-only table-valued function
** (a virtual table) designed to be used for testing. We are not aware
** of any practical real-world use case for the virtual table.
**
** This virtual table originated in the TH3 test suite. It is still used
** there, but has now been copied into the public SQLite source tree and
** reused for a variety of testing purpose. The name "vt02" comes from the
** fact that there are many different testing virtual tables in TH3, of which
** this one is the second.
**
** ## SUBJECT TO CHANGE
**
** Because this virtual table is intended for testing, its interface is not
** guaranteed to be stable across releases. Future releases may contain
** changes in the vt02 design and interface.
**
** ## OVERVIEW
**
** The vt02 table-valued function has 10000 rows with 5 data columns.
** Column X contains all integer values between 0 and 9999 inclusive.
** Columns A, B, C, and D contain the individual base-10 digits associated
** with each X value:
**
** X A B C D
** ---- - - - -
** 0 0 0 0 0
** 1 0 0 0 1
** 2 0 0 0 2
** ...
** 4998 4 9 9 8
** 4999 4 9 9 9
** 5000 5 0 0 0
** ...
** 9995 9 9 9 5
** 9996 9 9 9 6
** 9997 9 9 9 7
**
** The xBestIndex method recognizes a variety of equality constraints
** and attempts to optimize its output accordingly.
**
** x=...
** a=...
** a=... AND b=...
** a=... AND b=... AND c=...
** a=... AND b=... AND c=... AND d=...
**
** Various ORDER BY constraints are also recognized and consumed. The
** OFFSET constraint is recognized and consumed.
**
** ## TABLE-VALUED FUNCTION
**
** The vt02 virtual table is eponymous and has two hidden columns, meaning
** that it can functions a table-valued function. The two hidden columns
** are "flags" and "logtab", in that order. The "flags" column can be set
** to an integer where various bits enable or disable behaviors of the
** virtual table. The "logtab" can set to the name of an ordinary SQLite
** table into which is written information about each call to xBestIndex.
**
** The bits of "flags" are as follows:
**
** 0x01 Ignore the aConstraint[].usable flag. This might
** result in the xBestIndex method incorrectly using
** unusable entries in the aConstraint[] array, which
** should result in the SQLite core detecting and
** reporting that the virtual table is not behaving
** to spec.
**
** 0x02 Do not set the orderByConsumed flag, even if it
** could be set.
**
** 0x04 Do not consume the OFFSET constraint, if there is
** one. Instead, let the generated byte-code visit
** and ignore the first few columns of output.
**
** 0x08 Use sqlite3_mprintf() to allocate an idxStr string.
** The string is never used, but allocating it does
** test the idxStr deallocation logic inside of the
** SQLite core.
**
** 0x10 Cause the xBestIndex method to generate an idxNum
** that xFilter does not understand, thus causing
** the OP_VFilter opcode to raise an error.
**
** 0x20 Set the omit flag for all equality constraints on
** columns X, A, B, C, and D that are used to limit
** the search.
**
** 0x40 Add all constraints against X,A,B,C,D to the
** vector of results sent to xFilter. Only the first
** few are used, as required by idxNum.
**
** Because these flags take effect during xBestIndex, the RHS of the
** flag= constraint must be accessible. In other words, the RHS of flag=
** needs to be an integer literal, not another column of a join or a
** bound parameter.
**
** ## LOGGING OUTPUT
**
** If the "logtab" columns is set, then each call to the xBestIndex method
** inserts multiple rows into the table identified by "logtab". These
** rows collectively show the content of the sqlite3_index_info object and
** other context associated with the xBestIndex call.
**
** If the table named by "logtab" does not previously exist, it is created
** automatically. The schema for the logtab table is like this:
**
** CREATE TEMP TABLE vt02_log(
** bi INT, -- BestIndex call counter
** vn TEXT, -- Variable Name
** ix INT, -- Index or value
** cn TEXT, -- Column Name
** op INT, -- Opcode or "DESC" value
** ux INT, -- "Usable" flag
** ra BOOLEAN, -- Right-hand side Available.
** rhs ANY, -- Right-Hand Side value
** cs TEXT -- Collating Sequence for this constraint
** );
**
** Because logging happens during xBestIindex, the RHS value of "logtab" must
** be known to xBestIndex, which means it must be a string literal, not a
** column in a join, or a bound parameter.
**
** ## VIRTUAL TABLE SCHEMA
**
** CREATE TABLE vt02(
** x INT, -- integer between 0 and 9999 inclusive
** a INT, -- The 1000s digit
** b INT, -- The 100s digit
** c INT, -- The 10s digit
** d INT, -- The 1s digit
** flags INT HIDDEN, -- Option flags
** logtab TEXT HIDDEN, -- Name of table into which to log xBestIndex
** );
**
** ## COMPILING AND RUNNING
**
** This file can also be compiled separately as a loadable extension
** for SQLite (as long as the -DTH3_VERSION is not defined). To compile as a
** loadable extension do his:
**
** gcc -Wall -g -shared -fPIC -I. -DSQLITE_DEBUG vt02.c -o vt02.so
**
** Or on Windows:
**
** cl vt02.c -link -dll -out:vt02.dll
**
** Then load into the CLI using:
**
** .load ./vt02 sqlite3_vt02_init
**
** ## IDXNUM SUMMARY
**
** The xBestIndex method communicates the query plan to xFilter using
** the idxNum value, as follows:
**
** 0 unconstrained
** 1 X=argv[0]
** 2 A=argv[0]
** 3 A=argv[0], B=argv[1]
** 4 A=argv[0], B=argv[1], C=argv[2]
** 5 A=argv[0], B=argv[1], C=argv[2], D=argv[3]
** 6 A=argv[0], D IN argv[2]
** 7 A=argv[0], B=argv[2], D IN argv[3]
** 8 A=argv[0], B=argv[2], C=argv[3], D IN argv[4]
** 1x increment by 10
** 2x increment by 100
** 3x increment by 1000
** 1xx Use offset provided by argv[N]
*/
#ifndef TH3_VERSION
/* These bits for separate compilation as a loadable extension, only */
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#endif
/* Forward declarations */
typedef struct vt02_vtab vt02_vtab;
typedef struct vt02_cur vt02_cur;
/*
** The complete virtual table
*/
struct vt02_vtab {
sqlite3_vtab parent; /* Base clase. Must be first. */
sqlite3 *db; /* Database connection */
int busy; /* Currently running xBestIndex */
};
#define VT02_IGNORE_USABLE 0x0001 /* Ignore usable flags */
#define VT02_NO_SORT_OPT 0x0002 /* Do not do any sorting optimizations */
#define VT02_NO_OFFSET 0x0004 /* Omit the offset optimization */
#define VT02_ALLOC_IDXSTR 0x0008 /* Alloate an idxStr */
#define VT02_BAD_IDXNUM 0x0010 /* Generate an invalid idxNum */
/*
** A cursor
*/
struct vt02_cur {
sqlite3_vtab_cursor parent; /* Base class. Must be first */
sqlite3_int64 i; /* Current entry */
sqlite3_int64 iEof; /* Indicate EOF when reaching this value */
int iIncr; /* Amount by which to increment */
unsigned int mD; /* Mask of allowed D-column values */
};
/* The xConnect method */
int vt02Connect(
sqlite3 *db, /* The database connection */
void *pAux, /* Pointer to an alternative schema */
int argc, /* Number of arguments */
const char *const*argv, /* Text of the arguments */
sqlite3_vtab **ppVTab, /* Write the new vtab here */
char **pzErr /* Error message written here */
){
vt02_vtab *pVtab;
int rc;
const char *zSchema = (const char*)pAux;
static const char zDefaultSchema[] =
"CREATE TABLE x(x INT, a INT, b INT, c INT, d INT,"
" flags INT HIDDEN, logtab TEXT HIDDEN);";
#define VT02_COL_X 0
#define VT02_COL_A 1
#define VT02_COL_B 2
#define VT02_COL_C 3
#define VT02_COL_D 4
#define VT02_COL_FLAGS 5
#define VT02_COL_LOGTAB 6
#define VT02_COL_NONE 7
pVtab = sqlite3_malloc( sizeof(*pVtab) );
if( pVtab==0 ){
*pzErr = sqlite3_mprintf("out of memory");
return SQLITE_NOMEM;
}
memset(pVtab, 0, sizeof(*pVtab));
pVtab->db = db;
rc = sqlite3_declare_vtab(db, zSchema ? zSchema : zDefaultSchema);
if( rc ){
sqlite3_free(pVtab);
}else{
*ppVTab = &pVtab->parent;
}
return rc;
}
/* the xDisconnect method
*/
int vt02Disconnect(sqlite3_vtab *pVTab){
sqlite3_free(pVTab);
return SQLITE_OK;
}
/* Put an error message into the zErrMsg string of the virtual table.
*/
static void vt02ErrMsg(sqlite3_vtab *pVtab, const char *zFormat, ...){
va_list ap;
sqlite3_free(pVtab->zErrMsg);
va_start(ap, zFormat);
pVtab->zErrMsg = sqlite3_vmprintf(zFormat, ap);
va_end(ap);
}
/* Open a cursor for scanning
*/
static int vt02Open(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
vt02_cur *pCur;
pCur = sqlite3_malloc( sizeof(*pCur) );
if( pCur==0 ){
vt02ErrMsg(pVTab, "out of memory");
return SQLITE_NOMEM;
}
*ppCursor = &pCur->parent;
pCur->i = -1;
return SQLITE_OK;
}
/* Close a cursor
*/
static int vt02Close(sqlite3_vtab_cursor *pCursor){
vt02_cur *pCur = (vt02_cur*)pCursor;
sqlite3_free(pCur);
return SQLITE_OK;
}
/* Return TRUE if we are at the end of the BVS and there are
** no more entries.
*/
static int vt02Eof(sqlite3_vtab_cursor *pCursor){
vt02_cur *pCur = (vt02_cur*)pCursor;
return pCur->i<0 || pCur->i>=pCur->iEof;
}
/* Advance the cursor to the next row in the table
*/
static int vt02Next(sqlite3_vtab_cursor *pCursor){
vt02_cur *pCur = (vt02_cur*)pCursor;
do{
pCur->i += pCur->iIncr;
if( pCur->i<0 ) pCur->i = pCur->iEof;
}while( (pCur->mD & (1<<(pCur->i%10)))==0 && pCur->i<pCur->iEof );
return SQLITE_OK;
}
/* Rewind a cursor back to the beginning of its scan.
**
** Scanning is always increasing.
**
** idxNum
** 0 unconstrained
** 1 X=argv[0]
** 2 A=argv[0]
** 3 A=argv[0], B=argv[1]
** 4 A=argv[0], B=argv[1], C=argv[2]
** 5 A=argv[0], B=argv[1], C=argv[2], D=argv[3]
** 6 A=argv[0], D IN argv[2]
** 7 A=argv[0], B=argv[2], D IN argv[3]
** 8 A=argv[0], B=argv[2], C=argv[3], D IN argv[4]
** 1x increment by 10
** 2x increment by 100
** 3x increment by 1000
** 1xx Use offset provided by argv[N]
*/
static int vt02Filter(
sqlite3_vtab_cursor *pCursor, /* The cursor to rewind */
int idxNum, /* Search strategy */
const char *idxStr, /* Not used */
int argc, /* Not used */
sqlite3_value **argv /* Not used */
){
vt02_cur *pCur = (vt02_cur*)pCursor; /* The vt02 cursor */
int bUseOffset = 0; /* True to use OFFSET value */
int iArg = 0; /* argv[] values used so far */
int iOrigIdxNum = idxNum; /* Original value for idxNum */
pCur->iIncr = 1;
pCur->mD = 0x3ff;
if( idxNum>=100 ){
bUseOffset = 1;
idxNum -= 100;
}
if( idxNum<0 || idxNum>38 ) goto vt02_bad_idxnum;
while( idxNum>=10 ){
pCur->iIncr *= 10;
idxNum -= 10;
}
if( idxNum==0 ){
pCur->i = 0;
pCur->iEof = 10000;
}else if( idxNum==1 ){
pCur->i = sqlite3_value_int64(argv[0]);
if( pCur->i<0 ) pCur->i = -1;
if( pCur->i>9999 ) pCur->i = 10000;
pCur->iEof = pCur->i+1;
if( pCur->i<0 || pCur->i>9999 ) pCur->i = pCur->iEof;
}else if( idxNum>=2 && idxNum<=5 ){
int i, e, m;
e = idxNum - 2;
assert( e<=argc-1 );
pCur->i = 0;
for(m=1000, i=0; i<=e; i++, m /= 10){
sqlite3_int64 v = sqlite3_value_int64(argv[iArg++]);
if( v<0 ) v = 0;
if( v>9 ) v = 9;
pCur->i += m*v;
pCur->iEof = pCur->i+m;
}
}else if( idxNum>=6 && idxNum<=8 ){
int i, e, m, rc;
sqlite3_value *pIn, *pVal;
e = idxNum - 6;
assert( e<=argc-2 );
pCur->i = 0;
for(m=1000, i=0; i<=e; i++, m /= 10){
sqlite3_int64 v;
pVal = 0;
if( sqlite3_vtab_in_first(0, &pVal)!=SQLITE_MISUSE
|| sqlite3_vtab_in_first(argv[iArg], &pVal)!=SQLITE_ERROR
){
vt02ErrMsg(pCursor->pVtab,
"unexpected success from sqlite3_vtab_in_first()");
return SQLITE_ERROR;
}
v = sqlite3_value_int64(argv[iArg++]);
if( v<0 ) v = 0;
if( v>9 ) v = 9;
pCur->i += m*v;
pCur->iEof = pCur->i+m;
}
pCur->mD = 0;
pIn = argv[iArg++];
assert( sqlite3_value_type(pIn)==SQLITE_NULL );
for( rc = sqlite3_vtab_in_first(pIn, &pVal);
rc==SQLITE_OK && pVal!=0;
rc = sqlite3_vtab_in_next(pIn, &pVal)
){
int eType = sqlite3_value_numeric_type(pVal);
if( eType==SQLITE_FLOAT ){
double r = sqlite3_value_double(pVal);
if( r<0.0 || r>9.0 || r!=(int)r ) continue;
}else if( eType!=SQLITE_INTEGER ){
continue;
}
i = sqlite3_value_int(pVal);
if( i<0 || i>9 ) continue;
pCur->mD |= 1<<i;
}
if( rc!=SQLITE_OK && rc!=SQLITE_DONE ){
vt02ErrMsg(pCursor->pVtab, "Error from sqlite3_vtab_in_first/next()");
return rc;
}
}else{
goto vt02_bad_idxnum;
}
if( bUseOffset ){
int nSkip = sqlite3_value_int(argv[iArg]);
while( nSkip-- > 0 && pCur->i<pCur->iEof ) vt02Next(pCursor);
}
return SQLITE_OK;
vt02_bad_idxnum:
vt02ErrMsg(pCursor->pVtab, "invalid idxNum for vt02: %d", iOrigIdxNum);
return SQLITE_ERROR;
}
/* Return the Nth column of the current row.
*/
static int vt02Column(
sqlite3_vtab_cursor *pCursor,
sqlite3_context *context,
int N
){
vt02_cur *pCur = (vt02_cur*)pCursor;
int v = pCur->i;
if( N==VT02_COL_X ){
sqlite3_result_int(context, v);
}else if( N>=VT02_COL_A && N<=VT02_COL_D ){
static const int iDivisor[] = { 1, 1000, 100, 10, 1 };
v = (v/iDivisor[N])%10;
sqlite3_result_int(context, v);
}
return SQLITE_OK;
}
/* Return the rowid of the current row
*/
static int vt02Rowid(sqlite3_vtab_cursor *pCursor, sqlite3_int64 *pRowid){
vt02_cur *pCur = (vt02_cur*)pCursor;
*pRowid = pCur->i+1;
return SQLITE_OK;
}
/*************************************************************************
** Logging Subsystem
**
** The sqlite3BestIndexLog() routine implements a logging system for
** xBestIndex calls. This code is portable to any virtual table.
**
** sqlite3BestIndexLog() is the main routine, sqlite3RunSql() is a
** helper routine used for running various SQL statements as part of
** creating the log.
**
** These two routines should be portable to other virtual tables. Simply
** extract this code and call sqlite3BestIndexLog() near the end of the
** xBestIndex method in cases where logging is desired.
*/
/*
** Run SQL on behalf of sqlite3BestIndexLog.
**
** Construct the SQL using the zFormat string and subsequent arguments.
** Or if zFormat is NULL, take the SQL as the first argument after the
** zFormat. In either case, the dynamically allocated SQL string is
** freed after it has been run. If something goes wrong with the SQL,
** then an error is left in pVTab->zErrMsg.
*/
static void sqlite3RunSql(
sqlite3 *db, /* Run the SQL on this database connection */
sqlite3_vtab *pVTab, /* Report errors to this virtual table */
const char *zFormat, /* Format string for SQL, or NULL */
... /* Arguments, according to the format string */
){
char *zSql;
va_list ap;
va_start(ap, zFormat);
if( zFormat==0 ){
zSql = va_arg(ap, char*);
}else{
zSql = sqlite3_vmprintf(zFormat, ap);
}
va_end(ap);
if( zSql ){
char *zErrMsg = 0;
(void)sqlite3_exec(db, zSql, 0, 0, &zErrMsg);
if( zErrMsg ){
if( pVTab->zErrMsg==0 ){
pVTab->zErrMsg = sqlite3_mprintf("%s in [%s]", zErrMsg, zSql);
}
sqlite3_free(zErrMsg);
}
sqlite3_free(zSql);
}
}
/*
** Record information about each xBestIndex method call in a separate
** table:
**
** CREATE TEMP TABLE [log-table-name] (
** bi INT, -- BestIndex call number
** vn TEXT, -- Variable Name
** ix INT, -- Index or value
** cn TEXT, -- Column Name
** op INT, -- Opcode or argvIndex
** ux INT, -- "usable" or "omit" flag
** rx BOOLEAN, -- True if has a RHS value
** rhs ANY, -- The RHS value
** cs TEXT, -- Collating Sequence
** inop BOOLEAN -- True if this is a batchable IN operator
** );
**
** If an error occurs, leave an error message in pVTab->zErrMsg.
*/
static void sqlite3BestIndexLog(
sqlite3_index_info *pInfo, /* The sqlite3_index_info object */
const char *zLogTab, /* Log into this table */
sqlite3 *db, /* Database connection containing zLogTab */
const char **azColname, /* Names of columns in the virtual table */
sqlite3_vtab *pVTab /* Record errors into this object */
){
int i, rc;
sqlite3_str *pStr;
int iBI;
if( sqlite3_table_column_metadata(db,0,zLogTab,0,0,0,0,0,0) ){
/* The log table does not previously exist. Create it. */
sqlite3RunSql(db,pVTab,
"CREATE TABLE IF NOT EXISTS temp.\"%w\"(\n"
" bi INT, -- BestIndex call number\n"
" vn TEXT, -- Variable Name\n"
" ix INT, -- Index or value\n"
" cn TEXT, -- Column Name\n"
" op INT, -- Opcode or argvIndex\n"
" ux INT, -- usable for omit flag\n"
" rx BOOLEAN, -- Right-hand side value is available\n"
" rhs ANY, -- RHS value\n"
" cs TEXT, -- Collating Sequence\n"
" inop BOOLEAN -- IN operator capable of batch reads\n"
");", zLogTab
);
iBI = 1;
}else{
/* The log table does already exist. We assume that it has the
** correct schema and proceed to find the largest prior "bi" value.
** If the schema is wrong, errors might result. The code is able
** to deal with this. */
sqlite3_stmt *pStmt;
char *zSql;
zSql = sqlite3_mprintf("SELECT max(bi) FROM temp.\"%w\"",zLogTab);
if( zSql==0 ){
sqlite3_free(pVTab->zErrMsg);
pVTab->zErrMsg = sqlite3_mprintf("out of memory");
return;
}
rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
sqlite3_free(zSql);
if( rc ){
sqlite3_free(pVTab->zErrMsg);
pVTab->zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(db));
iBI = 0;
}else if( sqlite3_step(pStmt)==SQLITE_ROW ){
iBI = sqlite3_column_int(pStmt, 0)+1;
}else{
iBI = 1;
}
sqlite3_finalize(pStmt);
}
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix) VALUES(%d,'nConstraint',%d)"
"RETURNING iif(bi=%d,'ok',RAISE(ABORT,'wrong trigger'))",
/* The RETURNING clause checks to see that the returning trigger fired
** for the correct INSERT in the case of nested INSERT RETURNINGs. */
zLogTab, iBI, pInfo->nConstraint, iBI
);
for(i=0; i<pInfo->nConstraint; i++){
sqlite3_value *pVal;
char *zSql;
int iCol = pInfo->aConstraint[i].iColumn;
int op = pInfo->aConstraint[i].op;
const char *zCol;
if( op==SQLITE_INDEX_CONSTRAINT_LIMIT
|| op==SQLITE_INDEX_CONSTRAINT_OFFSET
){
zCol = "";
}else if( iCol<0 ){
zCol = "rowid";
}else{
zCol = azColname[iCol];
}
pStr = sqlite3_str_new(0);
sqlite3_str_appendf(pStr,
"INSERT INTO temp.\"%w\"(bi,vn,ix,cn,op,ux,rx,rhs,cs,inop)"
"VALUES(%d,'aConstraint',%d,%Q,%d,%d",
zLogTab, iBI,
i,
zCol,
op,
pInfo->aConstraint[i].usable);
pVal = 0;
rc = sqlite3_vtab_rhs_value(pInfo, i, &pVal);
assert( pVal!=0 || rc!=SQLITE_OK );
if( rc==SQLITE_OK ){
sqlite3_str_appendf(pStr,",1,?1");
}else{
sqlite3_str_appendf(pStr,",0,NULL");
}
sqlite3_str_appendf(pStr,",%Q,%d)",
sqlite3_vtab_collation(pInfo,i),
sqlite3_vtab_in(pInfo,i,-1));
zSql = sqlite3_str_finish(pStr);
if( zSql==0 ){
if( pVTab->zErrMsg==0 ) pVTab->zErrMsg = sqlite3_mprintf("out of memory");
}else{
sqlite3_stmt *pStmt = 0;
rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
if( rc ){
if( pVTab->zErrMsg==0 ){
pVTab->zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(db));
}
}else{
if( pVal ) sqlite3_bind_value(pStmt, 1, pVal);
sqlite3_step(pStmt);
rc = sqlite3_reset(pStmt);
if( rc && pVTab->zErrMsg==0 ){
pVTab->zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(db));
}
}
sqlite3_finalize(pStmt);
sqlite3_free(zSql);
}
}
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix) VALUES(%d,'nOrderBy',%d)",
zLogTab, iBI, pInfo->nOrderBy
);
for(i=0; i<pInfo->nOrderBy; i++){
int iCol = pInfo->aOrderBy[i].iColumn;
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix,cn,op)VALUES(%d,'aOrderBy',%d,%Q,%d)",
zLogTab, iBI,
i,
iCol>=0 ? azColname[iCol] : "rowid",
pInfo->aOrderBy[i].desc
);
}
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix) VALUES(%d,'sqlite3_vtab_distinct',%d)",
zLogTab, iBI, sqlite3_vtab_distinct(pInfo)
);
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix) VALUES(%d,'colUsed',%lld)",
zLogTab, iBI, pInfo->colUsed
);
for(i=0; i<pInfo->nConstraint; i++){
int iCol = pInfo->aConstraint[i].iColumn;
int op = pInfo->aConstraint[i].op;
const char *zCol;
if( op==SQLITE_INDEX_CONSTRAINT_LIMIT
|| op==SQLITE_INDEX_CONSTRAINT_OFFSET
){
zCol = "";
}else if( iCol<0 ){
zCol = "rowid";
}else{
zCol = azColname[iCol];
}
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix,cn,op,ux)"
"VALUES(%d,'aConstraintUsage',%d,%Q,%d,%d)",
zLogTab, iBI,
i,
zCol,
pInfo->aConstraintUsage[i].argvIndex,
pInfo->aConstraintUsage[i].omit
);
}
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix)VALUES(%d,'idxNum',%d)",
zLogTab, iBI, pInfo->idxNum
);
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix)VALUES(%d,'estimatedCost',%f)",
zLogTab, iBI, pInfo->estimatedCost
);
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix)VALUES(%d,'estimatedRows',%lld)",
zLogTab, iBI, pInfo->estimatedRows
);
if( pInfo->idxStr ){
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix)VALUES(%d,'idxStr',%Q)",
zLogTab, iBI, pInfo->idxStr
);
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix)VALUES(%d,'needToFreeIdxStr',%d)",
zLogTab, iBI, pInfo->needToFreeIdxStr
);
}
if( pInfo->nOrderBy ){
sqlite3RunSql(db,pVTab,
"INSERT INTO temp.\"%w\"(bi,vn,ix)VALUES(%d,'orderByConsumed',%d)",
zLogTab, iBI, pInfo->orderByConsumed
);
}
}
/*
** End of Logging Subsystem
*****************************************************************************/
/* Find an estimated cost of running a query against vt02.
*/
static int vt02BestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
int i; /* Loop counter */
int isEq[5]; /* Equality constraints on X, A, B, C, and D */
int isUsed[5]; /* Other non-== cosntraints X, A, B, C, and D */
int argvIndex = 0; /* Next available argv[] slot */
int iOffset = -1; /* Constraint for OFFSET */
void *pX = 0; /* idxStr value */
int flags = 0; /* RHS value for flags= */
const char *zLogTab = 0; /* RHS value for logtab= */
int iFlagTerm = -1; /* Constraint term for flags= */
int iLogTerm = -1; /* Constraint term for logtab= */
int iIn = -1; /* Index of the IN constraint */
vt02_vtab *pSelf; /* This virtual table */
pSelf = (vt02_vtab*)pVTab;
if( pSelf->busy ){
vt02ErrMsg(pVTab, "recursive use of vt02 prohibited");
return SQLITE_CONSTRAINT;
}
pSelf->busy++;
/* Do an initial scan for flags=N and logtab=TAB constraints with
** usable RHS values */
for(i=0; i<pInfo->nConstraint; i++){
sqlite3_value *pVal;
if( !pInfo->aConstraint[i].usable ) continue;
if( pInfo->aConstraint[i].op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
switch( pInfo->aConstraint[i].iColumn ){
case VT02_COL_FLAGS:
if( sqlite3_vtab_rhs_value(pInfo, i, &pVal)==SQLITE_OK
&& sqlite3_value_type(pVal)==SQLITE_INTEGER
){
flags = sqlite3_value_int(pVal);
}
iFlagTerm = i;
break;
case VT02_COL_LOGTAB:
if( sqlite3_vtab_rhs_value(pInfo, i, &pVal)==SQLITE_OK
&& sqlite3_value_type(pVal)==SQLITE_TEXT
){
zLogTab = (const char*)sqlite3_value_text(pVal);
}
iLogTerm = i;
break;
}
}
/* Do a second scan to actually analyze the index information */
memset(isEq, 0xff, sizeof(isEq));
memset(isUsed, 0xff, sizeof(isUsed));
for(i=0; i<pInfo->nConstraint; i++){
int j = pInfo->aConstraint[i].iColumn;
if( j>=VT02_COL_FLAGS ) continue;
if( pInfo->aConstraint[i].usable==0
&& (flags & VT02_IGNORE_USABLE)==0 ) continue;
if( j<0 ) j = VT02_COL_X;
switch( pInfo->aConstraint[i].op ){
case SQLITE_INDEX_CONSTRAINT_FUNCTION:
case SQLITE_INDEX_CONSTRAINT_EQ:
isEq[j] = i;
break;
case SQLITE_INDEX_CONSTRAINT_LT:
case SQLITE_INDEX_CONSTRAINT_LE:
case SQLITE_INDEX_CONSTRAINT_GT:
case SQLITE_INDEX_CONSTRAINT_GE:
isUsed[j] = i;
break;
case SQLITE_INDEX_CONSTRAINT_OFFSET:
iOffset = i;
break;
}
}
/* Use the analysis to find an appropriate query plan */
if( isEq[0]>=0 ){
/* A constraint of X= takes priority */
pInfo->estimatedCost = 1;
pInfo->aConstraintUsage[isEq[0]].argvIndex = ++argvIndex;
if( flags & 0x20 ) pInfo->aConstraintUsage[isEq[0]].omit = 1;
pInfo->idxNum = 1;
}else if( isEq[1]<0 ){
/* If there is no X= nor A= then we have to do a full scan */
pInfo->idxNum = 0;
pInfo->estimatedCost = 10000;
}else{
int v = 1000;
pInfo->aConstraintUsage[isEq[1]].argvIndex = ++argvIndex;
if( flags & 0x20 ) pInfo->aConstraintUsage[isEq[1]].omit = 1;
for(i=2; i<=4 && isEq[i]>=0; i++){
if( i==4 && sqlite3_vtab_in(pInfo, isEq[4], 0) ) break;
pInfo->aConstraintUsage[isEq[i]].argvIndex = ++argvIndex;
if( flags & 0x20 ) pInfo->aConstraintUsage[isEq[i]].omit = 1;
v /= 10;
}
pInfo->idxNum = i;
if( isEq[4]>=0 && sqlite3_vtab_in(pInfo,isEq[4],1) ){
iIn = isEq[4];
pInfo->aConstraintUsage[iIn].argvIndex = ++argvIndex;
if( flags & 0x20 ) pInfo->aConstraintUsage[iIn].omit = 1;
v /= 5;
i++;
pInfo->idxNum += 4;
}
pInfo->estimatedCost = v;
}
pInfo->estimatedRows = (sqlite3_int64)pInfo->estimatedCost;
/* Attempt to consume the ORDER BY clause. Except, always leave
** orderByConsumed set to 0 for vt02_no_sort_opt. In this way,
** we can compare vt02 and vt02_no_sort_opt to ensure they get
** the same answer.
*/
if( pInfo->nOrderBy>0 && (flags & VT02_NO_SORT_OPT)==0 ){
if( pInfo->idxNum==1 ){
/* There will only be one row of output. So it is always sorted. */
pInfo->orderByConsumed = 1;
}else
if( pInfo->aOrderBy[0].iColumn<=0
&& pInfo->aOrderBy[0].desc==0
){
/* First column of order by is X ascending */
pInfo->orderByConsumed = 1;
}else
if( sqlite3_vtab_distinct(pInfo)>=1 ){
unsigned int x = 0;
for(i=0; i<pInfo->nOrderBy; i++){
int iCol = pInfo->aOrderBy[i].iColumn;
if( iCol<0 ) iCol = 0;
x |= 1<<iCol;
}
if( sqlite3_vtab_distinct(pInfo)==2 ){
if( x==0x02 ){
/* DISTINCT A */
pInfo->idxNum += 30;
pInfo->orderByConsumed = 1;
}else if( x==0x06 ){
/* DISTINCT A,B */
pInfo->idxNum += 20;
pInfo->orderByConsumed = 1;
}else if( x==0x0e ){
/* DISTINCT A,B,C */
pInfo->idxNum += 10;
pInfo->orderByConsumed = 1;
}else if( x & 0x01 ){
/* DISTINCT X */
pInfo->orderByConsumed = 1;
}else if( x==0x1e ){
/* DISTINCT A,B,C,D */
pInfo->orderByConsumed = 1;
}
}else{
if( x==0x02 ){
/* GROUP BY A */
pInfo->orderByConsumed = 1;
}else if( x==0x06 ){
/* GROUP BY A,B */
pInfo->orderByConsumed = 1;
}else if( x==0x0e ){
/* GROUP BY A,B,C */
pInfo->orderByConsumed = 1;
}else if( x & 0x01 ){
/* GROUP BY X */
pInfo->orderByConsumed = 1;
}else if( x==0x1e ){
/* GROUP BY A,B,C,D */
pInfo->orderByConsumed = 1;
}
}
}
}
if( flags & VT02_ALLOC_IDXSTR ){
pInfo->idxStr = sqlite3_mprintf("test");
pInfo->needToFreeIdxStr = 1;
}
if( flags & VT02_BAD_IDXNUM ){
pInfo->idxNum += 1000;
}
if( iOffset>=0 ){
pInfo->aConstraintUsage[iOffset].argvIndex = ++argvIndex;
if( (flags & VT02_NO_OFFSET)==0
&& (pInfo->nOrderBy==0 || pInfo->orderByConsumed)
){
pInfo->aConstraintUsage[iOffset].omit = 1;
pInfo->idxNum += 100;
}
}
/* Always omit flags= and logtab= constraints to prevent them from
** interfering with the bytecode. Put them at the end of the argv[]
** array to keep them out of the way.
*/
if( iFlagTerm>=0 ){
pInfo->aConstraintUsage[iFlagTerm].omit = 1;
pInfo->aConstraintUsage[iFlagTerm].argvIndex = ++argvIndex;
}
if( iLogTerm>=0 ){
pInfo->aConstraintUsage[iLogTerm].omit = 1;
pInfo->aConstraintUsage[iLogTerm].argvIndex = ++argvIndex;
}
/* The 0x40 flag means add all usable constraints to the output set */
if( flags & 0x40 ){
for(i=0; i<pInfo->nConstraint; i++){
if( pInfo->aConstraint[i].usable
&& pInfo->aConstraintUsage[i].argvIndex==0
){
pInfo->aConstraintUsage[i].argvIndex = ++argvIndex;
if( flags & 0x20 ) pInfo->aConstraintUsage[i].omit = 1;
}
}
}
/* Generate the log if requested */
if( zLogTab ){
static const char *azColname[] = {
"x", "a", "b", "c", "d", "flags", "logtab"
};
sqlite3 *db = ((vt02_vtab*)pVTab)->db;
sqlite3BestIndexLog(pInfo, zLogTab, db, azColname, pVTab);
}
pSelf->busy--;
/* Try to do a memory allocation solely for the purpose of causing
** an error under OOM testing loops */
pX = sqlite3_malloc(800);
if( pX==0 ) return SQLITE_NOMEM;
sqlite3_free(pX);
return pVTab->zErrMsg!=0 ? SQLITE_ERROR : SQLITE_OK;
}
/* This is the sqlite3_module definition for the the virtual table defined
** by this include file.
*/
const sqlite3_module vt02Module = {
/* iVersion */ 2,
/* xCreate */ 0, /* This is an eponymous table */
/* xConnect */ vt02Connect,
/* xBestIndex */ vt02BestIndex,
/* xDisconnect */ vt02Disconnect,
/* xDestroy */ vt02Disconnect,
/* xOpen */ vt02Open,
/* xClose */ vt02Close,
/* xFilter */ vt02Filter,
/* xNext */ vt02Next,
/* xEof */ vt02Eof,
/* xColumn */ vt02Column,
/* xRowid */ vt02Rowid,
/* xUpdate */ 0,
/* xBegin */ 0,
/* xSync */ 0,
/* xCommit */ 0,
/* xRollback */ 0,
/* xFindFunction */ 0,
/* xRename */ 0,
/* xSavepoint */ 0,
/* xRelease */ 0,
/* xRollbackTo */ 0,
/* xShadowName */ 0,
/* xIntegrity */ 0
};
static void vt02CoreInit(sqlite3 *db){
static const char zPkXSchema[] =
"CREATE TABLE x(x INT NOT NULL PRIMARY KEY, a INT, b INT, c INT, d INT,"
" flags INT HIDDEN, logtab TEXT HIDDEN);";
static const char zPkABCDSchema[] =
"CREATE TABLE x(x INT, a INT NOT NULL, b INT NOT NULL, c INT NOT NULL, "
"d INT NOT NULL, flags INT HIDDEN, logtab TEXT HIDDEN, "
"PRIMARY KEY(a,b,c,d));";
sqlite3_create_module(db, "vt02", &vt02Module, 0);
sqlite3_create_module(db, "vt02pkx", &vt02Module, (void*)zPkXSchema);
sqlite3_create_module(db, "vt02pkabcd", &vt02Module, (void*)zPkABCDSchema);
}
#ifdef TH3_VERSION
static void vt02_init(th3state *p, int iDb, char *zArg){
vt02CoreInit(th3dbPointer(p, iDb));
}
#else
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_vt02_init(
sqlite3 *db,
char **pzErrMsg,
const sqlite3_api_routines *pApi
){
SQLITE_EXTENSION_INIT2(pApi);
vt02CoreInit(db);
return SQLITE_OK;
}
#endif /* TH3_VERSION */