-C Try\sto\spush\srelevant\sWHERE\sclause\sterms\sof\sthe\souter\squery\sdown\ninto\sthe\ssubquery\sin\sorder\sto\shelp\sthe\ssubquery\srun\sfaster\sand/or\s\nuse\sless\smemory.\s\s\sThis\sis\sa\scherry-pick\sof\s[6df18e949d36]\swith\nbug\sfixes.
-D 2017-07-17T19:37:23.434
+C Enhance\sthe\slike\soptimization\sso\sthat\sit\sworks\swith\san\sESCAPE\sclause.
+D 2017-07-27T22:16:26.706
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in 00d12636df7a5b08af09116bcd6c7bfd49b8b3b4
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
F src/expr.c d09dac67d53c78880ba31d56e8ba2be3a6490553
F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
F src/fkey.c e0444b61bed271a76840cbe6182df93a9baa3f12
-F src/func.c 1414c24c873c48796ad45942257a179a423ba42f
+F src/func.c 8028a8f79becc879268a114729263a24733ecdb610e7b7ec6ddb228bc2c13cf1
F src/global.c 4f77cadbc5427d00139ba43d0f3979804cbb700e
F src/hash.c 4263fbc955f26c2e8cdc0cf214bc42435aa4e4f5
F src/hash.h c8f3c31722cf3277d03713909761e152a5b81094
F src/wal.c 878c8e1a51cb2ec45c395d26b7d5cd9e1a098e4a
F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
F src/walker.c c253b95b4ee44b21c406e2a1052636c31ea27804
-F src/where.c 5e7cf96bd85f5e7cee1cce001031bc0ca1af68b8cfd07c781d1d8da7796eab34
+F src/where.c 3508f80b35073fbf384f6465337cd6820f333b1e8ec2ddb1478af43c4eec1eeb
F src/whereInt.h 1d1fd0b3b9b56e08f5d3583c70a2c785a3c43941
F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
F test/keyword1.test 37ef6bba5d2ed5b07ecdd6810571de2956599dff
F test/lastinsert.test 42e948fd6442f07d60acbd15d33fb86473e0ef63
F test/laststmtchanges.test ae613f53819206b3222771828d024154d51db200
-F test/like.test 4f2a71d36a536233727f71995fef900756705e56
+F test/like.test 1908852fc4a7bd2ebbe358648934f0e77b62569eca3ab0692ec2f1fa5ff59d0e
F test/like2.test 3b2ee13149ba4a8a60b59756f4e5d345573852da
F test/like3.test 7b0525a39e4f25c4fd113de7e2e28eb712dcdedf
F test/limit.test 0c99a27a87b14c646a9d583c7c89fd06c352663e
F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P d227de8ad9cf757f30f5415ca8fccff3b5959621d09244bd1f444d3282c5b2ef adc082c1461e0237cd42653b529fbc136f5899baeff6ee32ee943d76184080c1
-R a908a996bcff610704d1aca2821ce465
-T +closed adc082c1461e0237cd42653b529fbc136f5899baeff6ee32ee943d76184080c1
+P cd6ac0784898609ddca887cfb87c042cf409acbbe4e4e84bc5bc1f8528de74fd
+Q +f5d330f495d07a704e115595bbdf5422ddb68fd8191114c5a12c9c873d983f7c
+R 772fa82801a81bb4d46b7048641a4ff3
U drh
-Z 9d4148dec6ff72e63c10310b4326ef73
+Z c0ef846c292323e54ed21acdd6c2a147
-cd6ac0784898609ddca887cfb87c042cf409acbbe4e4e84bc5bc1f8528de74fd
\ No newline at end of file
+2495acf71017fa2ffada18824590ead593c47dabe2312701a25adc517cbf72eb
\ No newline at end of file
/*
** 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.
+** then set aWc[0] through aWc[2] to the wildcard characters and the
+** escape character and then return TRUE. If the function is not a
+** LIKE-style function then return FALSE.
+**
+** The expression "a LIKE b ESCAPE c" is only considered a valid LIKE
+** operator if c is a string literal that is exactly one byte in length.
+** That one byte is stored in aWc[3]. aWc[3] is set to zero if there is
+** no ESCAPE clause.
**
** *pIsNocase is set to true if uppercase and lowercase are equivalent for
** the function (default for LIKE). If the function makes the distinction
*/
int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
FuncDef *pDef;
- if( pExpr->op!=TK_FUNCTION
- || !pExpr->x.pList
- || pExpr->x.pList->nExpr!=2
- ){
+ int nExpr;
+ if( pExpr->op!=TK_FUNCTION || !pExpr->x.pList ){
return 0;
}
assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+ nExpr = pExpr->x.pList->nExpr;
pDef = sqlite3FindFunction(db, pExpr->u.zToken,
sqlite3Strlen30(pExpr->u.zToken),
- 2, SQLITE_UTF8, 0);
+ nExpr, SQLITE_UTF8, 0);
if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_FUNC_LIKE)==0 ){
return 0;
}
+ if( nExpr<3 ){
+ aWc[3] = 0;
+ }else{
+ Expr *pEscape = pExpr->x.pList->a[2].pExpr;
+ char *zEscape;
+ if( pEscape->op!=TK_STRING ) return 0;
+ zEscape = pEscape->u.zToken;
+ if( zEscape[0]==0 || zEscape[1]!=0 ) return 0;
+ aWc[3] = zEscape[0];
+ }
/* The memcpy() statement assumes that the wildcard characters are
** the first three statements in the compareInfo structure. The
ExprList *pList; /* List of operands to the LIKE operator */
int c; /* One character in z[] */
int cnt; /* Number of non-wildcard prefix characters */
- char wc[3]; /* Wildcard characters */
+ char wc[4]; /* Wildcard characters */
sqlite3 *db = pParse->db; /* Database connection */
sqlite3_value *pVal = 0;
int op; /* Opcode of pRight */
z = pRight->u.zToken;
}
if( z ){
+ /* Count the number of prefix characters prior to the first wildcard */
cnt = 0;
while( (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2] ){
cnt++;
+ if( c==wc[3] && z[cnt]!=0 ){
+ if( z[cnt++]>0xc0 ) while( (z[cnt]&0xc0)==0x80 ){ cnt++; }
+ }
}
+
+ /* The optimization is possible only if (1) the pattern does not begin
+ ** with a wildcard and if (2) the non-wildcard prefix does not end with
+ ** an (illegal 0xff) character. The second condition is necessary so
+ ** that we can increment the prefix key to find an upper bound for the
+ ** range search.
+ */
if( cnt!=0 && 255!=(u8)z[cnt-1] ){
Expr *pPrefix;
+
+ /* A "complete" match if the pattern ends with "*" or "%" */
*pisComplete = c==wc[0] && z[cnt+1]==0;
+
+ /* Get the pattern prefix. Remove all escapes from the prefix. */
pPrefix = sqlite3Expr(db, TK_STRING, z);
- if( pPrefix ) pPrefix->u.zToken[cnt] = 0;
+ if( pPrefix ){
+ int iFrom, iTo;
+ char *zNew = pPrefix->u.zToken;
+ zNew[cnt] = 0;
+ for(iFrom=iTo=0; iFrom<cnt; iFrom++){
+ if( zNew[iFrom]==wc[3] ) iFrom++;
+ zNew[iTo++] = zNew[iFrom];
+ }
+ zNew[iTo] = 0;
+ }
*ppPrefix = pPrefix;
+
+ /* If the RHS pattern is a bound parameter, make arrangements to
+ ** reprepare the statement when that parameter is rebound */
if( op==TK_VARIABLE ){
Vdbe *v = pParse->pVdbe;
sqlite3VdbeSetVarmask(v, pRight->iColumn);
} {/SCAN/}
+# As of 2017-07-27 (3.21.0) the LIKE optimization works with ESCAPE as
+# long as the ESCAPE is a single-byte literal.
+#
+db close
+sqlite3 db :memory:
+do_execsql_test like-15.100 {
+ CREATE TABLE t15(x TEXT COLLATE nocase, y, PRIMARY KEY(x));
+ INSERT INTO t15(x,y) VALUES
+ ('abcde',1), ('ab%de',2), ('a_cde',3),
+ ('uvwxy',11),('uvwx%',12),('uvwx_',13),
+ ('_bcde',21),('%bcde',22),
+ ('abcd_',31),('abcd%',32),
+ ('ab%xy',41);
+ SELECT y FROM t15 WHERE x LIKE 'ab/%d%' ESCAPE '/';
+} {2}
+do_execsql_test like-15.101 {
+ EXPLAIN QUERY PLAN
+ SELECT y FROM t15 WHERE x LIKE 'ab/%d%' ESCAPE '/';
+} {/SEARCH/}
+do_execsql_test like-15.102 {
+ EXPLAIN QUERY PLAN
+ SELECT y FROM t15 WHERE x LIKE 'ab/%d%' ESCAPE '//';
+} {/SCAN/}
+do_execsql_test like-15.103 {
+ EXPLAIN QUERY PLAN
+ SELECT y FROM t15 WHERE x LIKE 'ab/%d%' ESCAPE '';
+} {/SCAN/}
+do_execsql_test like-15.110 {
+ SELECT y FROM t15 WHERE x LIKE 'abcdx%%' ESCAPE 'x';
+} {32}
+do_execsql_test like-15.111 {
+ SELECT y FROM t15 WHERE x LIKE 'abx%%' ESCAPE 'x' ORDER BY +y
+} {2 41}
+do_execsql_test like-15.112 {
+ EXPLAIN QUERY PLAN
+ SELECT y FROM t15 WHERE x LIKE 'abx%%' ESCAPE 'x' ORDER BY +y
+} {/SEARCH/}
+do_execsql_test like-15.120 {
+ SELECT y FROM t15 WHERE x LIKE '/%bc%' ESCAPE '/';
+} {22}
+do_execsql_test like-15.121 {
+ EXPLAIN QUERY PLAN
+ SELECT y FROM t15 WHERE x LIKE '/%bc%' ESCAPE '/';
+} {/SEARCH/}
+
finish_test
projects / thirdparty / sqlite.git / commitdiff
