SQLite

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains functions used to access the internal hash tables
** of user defined functions and collation sequences.
**
** $Id: callback.c,v 1.3 2005/08/14 01:20:38 drh Exp $
*/

#include "sqliteInt.h"

/*
** Invoke the 'collation needed' callback to request a collation sequence
** in the database text encoding of name zName, length nName.

** array of three CollSeq structures. The first is the collation sequence
** prefferred for UTF-8, the second UTF-16le, and the third UTF-16be.
**
** Stored immediately after the three collation sequences is a copy of
** the collation sequence name. A pointer to this string is stored in
** each collation sequence structure.
*/
static CollSeq *findCollSeqEntry(
  sqlite3 *db,
  const char *zName,
  int nName,
  int create
){
  CollSeq *pColl;
  if( nName<0 ) nName = strlen(zName);

  }

  /* If the createFlag parameter is true, and the seach did not reveal an
  ** exact match for the name, number of arguments and encoding, then add a
  ** new entry to the hash table and return it.
  */
  if( createFlag && bestmatch<6 && 
      (pBest = sqliteMalloc(sizeof(*pBest)+nName)) ){
    pBest->nArg = nArg;
    pBest->pNext = pFirst;

    pBest->iPrefEnc = enc;
    memcpy(pBest->zName, zName, nName);
    pBest->zName[nName] = 0;
    if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
      sqliteFree(pBest);
      return 0;
    }

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.104 2005/08/14 01:20:38 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"
#include "os.h"

/*
** Return the collating function associated with a function.
*/
static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){
  return context->pColl;
}

/*
** Implementation of the non-aggregate min() and max() functions
*/

*/
struct compareInfo {
  u8 matchAll;
  u8 matchOne;
  u8 matchSet;
  u8 noCase;
};

static const struct compareInfo globInfo = { '*', '?', '[', 0 };

/* The correct SQL-92 behavior is for the LIKE operator to ignore
** case.  Thus  'a' LIKE 'A' would be true. */
static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };

/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
** is case sensitive causing 'a' LIKE 'A' to be false */
static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };


/*
** X is a pointer to the first byte of a UTF-8 character.  Increment
** X so that it points to the next character.  This only works right
** if X points to a well-formed UTF-8 string.
*/
#define sqliteNextChar(X)  while( (0xc0&*++(X))==0x80 ){}

      zString++;
      prevEscape = 0;
    }
  }
  return *zString==0;
}

/*
** Count the number of times that the LIKE operator (or GLOB which is
** just a variation of LIKE) gets called.  This is used for testing
** only.
*/
#ifdef SQLITE_TEST
int sqlite3_like_count = 0;
#endif


/*
** Implementation of the like() SQL function.  This function implements
** the build-in LIKE operator.  The first argument to the function is the
** pattern and the second argument is the string.  So, the SQL statements:
**
**       A LIKE B
**
** is implemented as like(B,A).
**
** This same function (with a different compareInfo structure) computes
** the GLOB operator.
*/
static void likeFunc(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv
){
  const unsigned char *zA = sqlite3_value_text(argv[0]);

      sqlite3_result_error(context, 
          "ESCAPE expression must be a single character", -1);
      return;
    }
    escape = sqlite3ReadUtf8(zEsc);
  }
  if( zA && zB ){
    struct compareInfo *pInfo = sqlite3_user_data(context);


#ifdef SQLITE_TEST










    sqlite3_like_count++;

#endif
    sqlite3_result_int(context, patternCompare(zA, zB, pInfo, escape));
  }
}

/*
** Implementation of the NULLIF(x,y) function.  The result is the first
** argument if the arguments are different.  The result is NULL if the
** arguments are equal to each other.

    { "upper",              1, 0, SQLITE_UTF8,    0, upperFunc  },
    { "lower",              1, 0, SQLITE_UTF8,    0, lowerFunc  },
    { "coalesce",          -1, 0, SQLITE_UTF8,    0, ifnullFunc },
    { "coalesce",           0, 0, SQLITE_UTF8,    0, 0          },
    { "coalesce",           1, 0, SQLITE_UTF8,    0, 0          },
    { "ifnull",             2, 0, SQLITE_UTF8,    1, ifnullFunc },
    { "random",            -1, 0, SQLITE_UTF8,    0, randomFunc },



    { "nullif",             2, 0, SQLITE_UTF8,    1, nullifFunc },
    { "sqlite_version",     0, 0, SQLITE_UTF8,    0, versionFunc},
    { "quote",              1, 0, SQLITE_UTF8,    0, quoteFunc  },
    { "last_insert_rowid",  0, 1, SQLITE_UTF8,    0, last_insert_rowid },
    { "changes",            0, 1, SQLITE_UTF8,    0, changes    },
    { "total_changes",      0, 1, SQLITE_UTF8,    0, total_changes },
#ifdef SQLITE_SOUNDEX

      if( pFunc && aAggs[i].needCollSeq ){
        pFunc->needCollSeq = 1;
      }
    }
  }
  sqlite3RegisterDateTimeFunctions(db);
#ifdef SQLITE_SSE
  sqlite3SseFunctions(db);
#endif
#ifdef SQLITE_CASE_SENSITIVE_LIKE
  sqlite3RegisterLikeFunctions(db, 1);
#else
  sqlite3RegisterLikeFunctions(db, 0);
#endif
}

/*
** Set the LIKEOPT flag on the 2-argument function with the given name.
*/
static void setLikeOptFlag(sqlite3 *db, const char *zName){
  FuncDef *pDef;
  pDef = sqlite3FindFunction(db, zName, strlen(zName), 2, SQLITE_UTF8, 0);
  if( pDef ){
    pDef->flags = SQLITE_FUNC_LIKEOPT;
  }
}

/*
** Register the built-in LIKE and GLOB functions.  The caseSensitive
** parameter determines whether or not the LIKE operator is case
** sensitive.  GLOB is always case sensitive.
*/
void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){
  struct compareInfo *pInfo;
  if( caseSensitive ){
    pInfo = (struct compareInfo*)&likeInfoAlt;
  }else{
    pInfo = (struct compareInfo*)&likeInfoNorm;
  }
  sqlite3_create_function(db, "like", 2, SQLITE_UTF8, pInfo, likeFunc, 0, 0);
  sqlite3_create_function(db, "like", 3, SQLITE_UTF8, pInfo, likeFunc, 0, 0);
  sqlite3_create_function(db, "glob", 2, SQLITE_UTF8, 
      (struct compareInfo*)&globInfo, likeFunc, 0,0);
  setLikeOptFlag(db, "glob");
  if( caseSensitive ){
    setLikeOptFlag(db, "like");
  }
}

/*
** pExpr points to an expression which implements a function.  If
** it is appropriate to apply the LIKE optimization to that function
** then set aWc[0] through aWc[2] to the wildcard characters and
** return TRUE.  If the function is not a LIKE-style function then
** return FALSE.
*/
int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, char *aWc){
  FuncDef *pDef;
  if( pExpr->op!=TK_FUNCTION ){
    return 0;
  }
  if( pExpr->pList->nExpr!=2 ){
    return 0;
  }
  pDef = sqlite3FindFunction(db, pExpr->token.z, pExpr->token.n, 2,
                             SQLITE_UTF8, 0);
  if( pDef==0 || (pDef->flags & SQLITE_FUNC_LIKEOPT)==0 ){
    return 0;
  }

  /* The memcpy() statement assumes that the wildcard characters are
  ** the first three statements in the compareInfo structure.  The
  ** asserts() that follow verify that assumption
  */
  memcpy(aWc, pDef->pUserData, 3);
  assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll );
  assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne );
  assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet );

  return 1;
}

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.298 2005/08/14 01:20:39 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The following constant value is used by the SQLITE_BIGENDIAN and

    }else{
      sqlite3ExpirePreparedStatements(db);
    }
  }

  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
  if( p==0 ) return SQLITE_NOMEM;
  p->flags = 0;
  p->xFunc = xFunc;
  p->xStep = xStep;
  p->xFinalize = xFinal;
  p->pUserData = pUserData;
  return SQLITE_OK;
}
#ifndef SQLITE_OMIT_UTF16

/*
** 2003 April 6
**
** 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 file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.98 2005/08/14 01:20:39 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/

    }
  }else
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */

#ifndef NDEBUG
  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
    extern void sqlite3ParserTrace(FILE*, char *);
    if( zRight ){
      if( getBoolean(zRight) ){
        sqlite3ParserTrace(stderr, "parser: ");
      }else{
        sqlite3ParserTrace(0, 0);
      }
    }
  }else
#endif

  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
  ** used will be case sensitive or not depending on the RHS.
  */
  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
    if( zRight ){
      sqlite3RegisterLikeFunctions(db, getBoolean(zRight));
    }
  }else

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
  if( sqlite3StrICmp(zLeft, "integrity_check")==0 ){
    int i, j, addr;

    /* Code that initializes the integrity check program.  Set the
    ** error count 0

/*
** 2001 September 15
**
** 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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.402 2005/08/14 01:20:39 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks

/*
** Each SQL function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct FuncDef {

  i16 nArg;            /* Number of arguments.  -1 means unlimited */
  u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
  u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
  u8 flags;            /* Some combination of SQLITE_FUNC_* */
  void *pUserData;     /* User data parameter */
  FuncDef *pNext;      /* Next function with same name */
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
  void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
  void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
  char zName[1];       /* SQL name of the function.  MUST BE LAST */
};

/*
** Possible values for FuncDef.flags
*/
#define SQLITE_FUNC_LIKEOPT  0x01    /* Candidate for the LIKE optimization */

/*
** information about each column of an SQL table is held in an instance
** of this structure.
*/
struct Column {
  char *zName;     /* Name of this column */
  Expr *pDflt;     /* Default value of this column */

CollSeq *sqlite3GetCollSeq(sqlite3*, CollSeq *, const char *, int);
char sqlite3AffinityType(const Token*);
void sqlite3Analyze(Parse*, Token*, Token*);
int sqlite3InvokeBusyHandler(BusyHandler*);
int sqlite3FindDb(sqlite3*, Token*);
void sqlite3AnalysisLoad(sqlite3*,int iDB);
void sqlite3DefaultRowEst(Index*);
void sqlite3RegisterLikeFunctions(sqlite3*, int);
int sqlite3IsLikeFunction(sqlite3*,Expr*,char*);

#ifdef SQLITE_SSE
#include "sseInt.h"
#endif

#endif

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the printf() interface to SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.154 2005/08/14 01:20:39 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

  Tcl_SetVar2(interp, "sqlite_options", "autovacuum", "1", TCL_GLOBAL_ONLY);
#endif /* SQLITE_OMIT_AUTOVACUUM */
#if !defined(SQLITE_DEFAULT_AUTOVACUUM) || SQLITE_DEFAULT_AUTOVACUUM==0
  Tcl_SetVar2(interp,"sqlite_options","default_autovacuum","0",TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp,"sqlite_options","default_autovacuum","1",TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_BETWEEN_OPTIMIZATION
  Tcl_SetVar2(interp, "sqlite_options", "between_opt", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "between_opt", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_BLOB_LITERAL
  Tcl_SetVar2(interp, "sqlite_options", "bloblit", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "bloblit", "1", TCL_GLOBAL_ONLY);
#endif

#endif

#ifdef SQLITE_OMIT_INTEGRITY_CHECK
  Tcl_SetVar2(interp, "sqlite_options", "integrityck", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "integrityck", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_LIKE_OPTIMIZATION
  Tcl_SetVar2(interp, "sqlite_options", "like_opt", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "like_opt", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_MEMORYDB
  Tcl_SetVar2(interp, "sqlite_options", "memorydb", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "memorydb", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_OR_OPTIMIZATION
  Tcl_SetVar2(interp, "sqlite_options", "or_opt", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "or_opt", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_PAGER_PRAGMAS
  Tcl_SetVar2(interp, "sqlite_options", "pager_pragmas", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "pager_pragmas", "1", TCL_GLOBAL_ONLY);
#endif

  extern int sqlite3_os_trace;
  extern int sqlite3_where_trace;
  extern int sqlite3_sync_count, sqlite3_fullsync_count;
  extern int sqlite3_opentemp_count;
  extern int sqlite3_memUsed;
  extern int sqlite3_memMax;
  extern char sqlite3_query_plan[];
  extern int sqlite3_like_count;
  static char *query_plan = sqlite3_query_plan;

  for(i=0; i<sizeof(aCmd)/sizeof(aCmd[0]); i++){
    Tcl_CreateCommand(interp, aCmd[i].zName, aCmd[i].xProc, 0, 0);
  }
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, 
        aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
  }
  Tcl_LinkVar(interp, "sqlite_search_count", 
      (char*)&sqlite3_search_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_sort_count", 
      (char*)&sqlite3_sort_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_like_count", 
      (char*)&sqlite3_like_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_interrupt_count", 
      (char*)&sqlite3_interrupt_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_open_file_count", 
      (char*)&sqlite3_open_file_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_current_time", 
      (char*)&sqlite3_current_time, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_os_trace",

  }
  pOp = &p->aOp[i];
  pOp->opcode = op;
  pOp->p1 = p1;
  pOp->p2 = p2;
  pOp->p3 = 0;
  pOp->p3type = P3_NOTUSED;
  p->expired = 0;
#ifdef SQLITE_DEBUG
  if( sqlite3_vdbe_addop_trace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
#endif
  return i;
}

/*

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.162 2005/08/14 01:20:39 drh Exp $
*/
#include "sqliteInt.h"

/*
** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
*/
#define BMS  (sizeof(Bitmask)*8)

** can be optimized using inequality constraints.  Return TRUE if it is
** so and false if not.
**
** In order for the operator to be optimizible, the RHS must be a string
** literal that does not begin with a wildcard.  
*/
static int isLikeOrGlob(
  sqlite3 *db,      /* The database */
  Expr *pExpr,      /* Test this expression */
  int *pnPattern,   /* Number of non-wildcard prefix characters */
  int *pisComplete  /* True if the only wildcard is % in the last character */
){
  const char *z;
  Expr *pRight, *pLeft;
  ExprList *pList;
  int c, cnt;
  char wc[3];
  if( !sqlite3IsLikeFunction(db, pExpr, wc) ){
    return 0;
  }
  pList = pExpr->pList;





















  pRight = pList->a[0].pExpr;
  if( pRight->op!=TK_STRING ){
    return 0;
  }
  pLeft = pList->a[1].pExpr;
  if( pLeft->op!=TK_COLUMN ){
    return 0;
  }
  sqlite3DequoteExpr(pRight);
  z = pRight->token.z;
  for(cnt=0; (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2]; cnt++){}
  if( cnt==0 || 255==(u8)z[cnt] ){
    return 0;
  }
  *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
  *pnPattern = cnt;
  return 1;
}
#endif /* SQLITE_OMIT_LIKE_OPTIMIZATION */

/*
** The input to this routine is an WhereTerm structure with only the

  }
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */

#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
  /* Add constraints to reduce the search space on a LIKE or GLOB
  ** operator.
  */
  if( isLikeOrGlob(pTerm->pWC->pParse->db, pExpr, &nPattern, &isComplete) ){
    Expr *pLeft, *pRight;
    Expr *pStr1, *pStr2;
    Expr *pNewExpr1, *pNewExpr2;
    WhereTerm *pNewTerm1, *pNewTerm2;
    pLeft = pExpr->pList->a[1].pExpr;
    pRight = pExpr->pList->a[0].pExpr;
    pStr1 = sqlite3Expr(TK_STRING, 0, 0, 0);

# 2005 August 13
#
# 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 file implements regression tests for SQLite library.  The
# focus of this file is testing the LIKE and GLOB operators and
# in particular the optimizations that occur to help those operators
# run faster.
#
# $Id: like.test,v 1.1 2005/08/14 01:20:40 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Create some sample data to work with.
#
do_test like-1.0 {
  execsql {
    CREATE TABLE t1(x TEXT);
  }
  foreach str {
    a
    ab
    abc
    abcd

    acd
    abd
    bc
    bcd

    xyz
    ABC
    CDE
    {ABC abc xyz}
  } {
    db eval {INSERT INTO t1 VALUES($str)}
  }
  execsql {
    SELECT count(*) FROM t1;
  }
} {12}

# Test that both case sensitive and insensitive version of LIKE work.
#
do_test like-1.1 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'abc' ORDER BY 1;
  }
} {ABC abc}
do_test like-1.2 {
  execsql {
    SELECT x FROM t1 WHERE x GLOB 'abc' ORDER BY 1;
  }
} {abc}
do_test like-1.3 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'ABC' ORDER BY 1;
  }
} {ABC abc}
do_test like-1.4 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'aBc' ORDER BY 1;
  }
} {ABC abc}
do_test like-1.5 {
  execsql {
    PRAGMA case_sensitive_like=on;
    SELECT x FROM t1 WHERE x LIKE 'abc' ORDER BY 1;
  }
} {abc}
do_test like-1.6 {
  execsql {
    SELECT x FROM t1 WHERE x GLOB 'abc' ORDER BY 1;
  }
} {abc}
do_test like-1.7 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'ABC' ORDER BY 1;
  }
} {ABC}
do_test like-1.8 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'aBc' ORDER BY 1;
  }
} {}
do_test like-1.9 {
  execsql {
    PRAGMA case_sensitive_like=off;
    SELECT x FROM t1 WHERE x LIKE 'abc' ORDER BY 1;
  }
} {ABC abc}

# Tests of the REGEXP operator
#
do_test like-2.1 {
  proc test_regexp {a b} {
    return [regexp $a $b]
  }
  db function regexp test_regexp
  execsql {
    SELECT x FROM t1 WHERE x REGEXP 'abc' ORDER BY 1;
  }
} {{ABC abc xyz} abc abcd}
do_test like-2.2 {
  execsql {
    SELECT x FROM t1 WHERE x REGEXP '^abc' ORDER BY 1;
  }
} {abc abcd}

# For the remaining tests, we need to have the like optimizations
# enabled.
#
ifcapable !like_opt {
  finish_test
  return
} 

# This procedure executes the SQL.  Then it appends to the result the
# "sort" or "nosort" keyword (as in the cksort procedure above) then
# it appends the ::sqlite_query_plan variable.
#
proc queryplan {sql} {
  set ::sqlite_sort_count 0
  set data [execsql $sql]
  if {$::sqlite_sort_count} {set x sort} {set x nosort}
  lappend data $x
  return [concat $data $::sqlite_query_plan]
}

# Perform tests on the like optimization.
#
# With no index on t1.x and with case sensitivity turned off, no optimization
# is performed.
#
do_test like-3.1 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {ABC {ABC abc xyz} abc abcd sort t1 {}}
do_test like-3.2 {
  set sqlite_like_count
} {12}

# With an index on t1.x and case sensitivity on, optimize completely.
#
do_test like-3.3 {
  set sqlite_like_count 0
  execsql {
    PRAGMA case_sensitive_like=on;
    CREATE INDEX i1 ON t1(x);
  }
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.4 {
  set sqlite_like_count
} 0

# Partial optimization when the pattern does not end in '%'
#
do_test like-3.5 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'a_c' ORDER BY 1;
  }
} {abc nosort {} i1}
do_test like-3.6 {
  set sqlite_like_count
} 6
do_test like-3.7 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'ab%d' ORDER BY 1;
  }
} {abcd abd nosort {} i1}
do_test like-3.8 {
  set sqlite_like_count
} 4
do_test like-3.9 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'a_c%' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.10 {
  set sqlite_like_count
} 6

# No optimization when the pattern begins with a wildcard.
# Note that the index is still used but only for sorting.
#
do_test like-3.11 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE '%bcd' ORDER BY 1;
  }
} {abcd bcd nosort {} i1}
do_test like-3.12 {
  set sqlite_like_count
} 12

# No optimization for case insensitive LIKE
#
do_test like-3.13 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=off;
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {ABC {ABC abc xyz} abc abcd nosort {} i1}
do_test like-3.14 {
  set sqlite_like_count
} 12

# No optimization without an index.
#
do_test like-3.15 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=on;
    DROP INDEX i1;
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {abc abcd sort t1 {}}
do_test like-3.16 {
  set sqlite_like_count
} 12

# No GLOB optimization without an index.
#
do_test like-3.17 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x GLOB 'abc*' ORDER BY 1;
  }
} {abc abcd sort t1 {}}
do_test like-3.18 {
  set sqlite_like_count
} 12

# GLOB is optimized regardless of the case_sensitive_like setting.
#
do_test like-3.19 {
  set sqlite_like_count 0
  queryplan {
    CREATE INDEX i1 ON t1(x);
    SELECT x FROM t1 WHERE x GLOB 'abc*' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.20 {
  set sqlite_like_count
} 0
do_test like-3.21 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=on;
    SELECT x FROM t1 WHERE x GLOB 'abc*' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.22 {
  set sqlite_like_count
} 0
do_test like-3.23 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=off;
    SELECT x FROM t1 WHERE x GLOB 'a[bc]d' ORDER BY 1;
  }
} {abd acd nosort {} i1}
do_test like-3.24 {
  set sqlite_like_count
} 6

finish_test