SQLite

Check-in [b4a9e09e]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Refactor the LIKE optimization decision logic so that it uses sqlite3AtoF() on both boundary keys to determine if the optimization can be used when the LHS is something that might not have TEXT affinity. Ticket [ce8717f0885af975]. See also [c94369cae9b561b1], [b043a54c3de54b28], [fd76310a5e843e07], and [158290c0abafde67].
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA3-256: b4a9e09e60213ccff925d09f0b6e549e2a3e3862856c710f108779e2867dec76
User & Date: drh 2019-06-14 12:28:21
Context
2019-06-14
13:24
Fix the implementation of the built-in RTRIM collating sequence so that it works for control characters at the end of the string. Ticket [f1580ba1b574e9e9] (check-in: 86fa0087 user: drh tags: trunk)
12:28
Refactor the LIKE optimization decision logic so that it uses sqlite3AtoF() on both boundary keys to determine if the optimization can be used when the LHS is something that might not have TEXT affinity. Ticket [ce8717f0885af975]. See also [c94369cae9b561b1], [b043a54c3de54b28], [fd76310a5e843e07], and [158290c0abafde67]. (check-in: b4a9e09e user: drh tags: trunk)
2019-06-13
16:14
Add a new requirement mark on the ctime.c code. (check-in: c4b40568 user: drh tags: trunk)
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/whereexpr.c.

260
261
262
263
264
265
266
267
268

269
270
271
272
273


274
275
276
277
278
279
280
281
282
283
284
285
286
287
288









289
290
291
292
293
294
295
        for(iFrom=iTo=0; iFrom<cnt; iFrom++){
          if( zNew[iFrom]==wc[3] ) iFrom++;
          zNew[iTo++] = zNew[iFrom];
        }
        zNew[iTo] = 0;
        assert( iTo>0 );

        /* If the RHS begins with a digit, a +/- sign or whitespace, then the
        ** LHS must be an ordinary column (not a virtual table column) with

        ** TEXT affinity. Otherwise the LHS might be numeric and "lhs >= rhs"
        ** would be false even though "lhs LIKE rhs" is true.  But if the RHS
        ** does not start with a digit or +/-, then "lhs LIKE rhs" will always
        ** be false if the LHS is numeric and so the optimization still works.
        **


        ** 2018-09-10 ticket c94369cae9b561b1f996d0054bfab11389f9d033
        ** The RHS pattern must not be '/%' because the termination condition
        ** will then become "x<'0'" and if the affinity is numeric, will then
        ** be converted into "x<0", which is incorrect.
        */
        if( sqlite3Isdigit(zNew[0])
         || sqlite3Isspace(zNew[0])
         || zNew[0]=='-'
         || zNew[0]=='+'
         || zNew[iTo-1]=='0'-1
        ){
          if( pLeft->op!=TK_COLUMN 
           || sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT 
           || IsVirtual(pLeft->y.pTab)  /* Value might be numeric */
          ){









            sqlite3ExprDelete(db, pPrefix);
            sqlite3ValueFree(pVal);
            return 0;
          }
        }
      }
      *ppPrefix = pPrefix;







<
|
>
|
<
<
|

>
>
|
|
|
|

<
<
<
<
<
<
|
|
|
|
>
>
>
>
>
>
>
>
>







260
261
262
263
264
265
266

267
268
269


270
271
272
273
274
275
276
277
278






279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
        for(iFrom=iTo=0; iFrom<cnt; iFrom++){
          if( zNew[iFrom]==wc[3] ) iFrom++;
          zNew[iTo++] = zNew[iFrom];
        }
        zNew[iTo] = 0;
        assert( iTo>0 );


        /* If the LHS is not an ordinary column with TEXT affinity, then the
        ** pattern prefix boundaries (both the start and end boundaries) must
        ** not look like a number.  Otherwise the pattern might be treated as


        ** a number, which will invalidate the LIKE optimization.
        **
        ** Getting this right has been a persistent source of bugs in the
        ** LIKE optimization.  See, for example:
        **    2018-09-10 https://sqlite.org/src/info/c94369cae9b561b1
        **    2019-05-02 https://sqlite.org/src/info/b043a54c3de54b28
        **    2019-06-10 https://sqlite.org/src/info/fd76310a5e843e07
        **    2019-06-14 https://sqlite.org/src/info/ce8717f0885af975
        */






        if( pLeft->op!=TK_COLUMN 
         || sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT 
         || IsVirtual(pLeft->y.pTab)  /* Value might be numeric */
        ){
          int isNum;
          double rDummy;
          isNum = sqlite3AtoF(zNew, &rDummy, iTo, SQLITE_UTF8);
          if( isNum<=0 ){
            zNew[iTo-1]++;
            isNum = sqlite3AtoF(zNew, &rDummy, iTo, SQLITE_UTF8);
            zNew[iTo-1]--;
          }
          if( isNum>0 ){
            sqlite3ExprDelete(db, pPrefix);
            sqlite3ValueFree(pVal);
            return 0;
          }
        }
      }
      *ppPrefix = pPrefix;

Changes to test/like3.test.

193
194
195
196
197
198
199









200
201
202
203
204
205
206
#
do_execsql_test like3-5.400 {
  DROP TABLE IF EXISTS t0;
  CREATE TABLE t0(c0 INT UNIQUE COLLATE NOCASE);
  INSERT INTO t0(c0) VALUES ('./');
  SELECT * FROM t0 WHERE t0.c0 LIKE './';
} {./}











# 2019-02-27
# Verify that the LIKE optimization works with an ESCAPE clause when
# using PRAGMA case_sensitive_like=ON.
#
ifcapable !icu {







>
>
>
>
>
>
>
>
>







193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
#
do_execsql_test like3-5.400 {
  DROP TABLE IF EXISTS t0;
  CREATE TABLE t0(c0 INT UNIQUE COLLATE NOCASE);
  INSERT INTO t0(c0) VALUES ('./');
  SELECT * FROM t0 WHERE t0.c0 LIKE './';
} {./}

# 2019-06-14
# Ticket https://www.sqlite.org/src/info/ce8717f0885af975
do_execsql_test like3-5.410 {
  DROP TABLE IF EXISTS t0;
  CREATE TABLE t0(c0 INT UNIQUE COLLATE NOCASE);
  INSERT INTO t0(c0) VALUES ('.1%');
  SELECT * FROM t0 WHERE t0.c0 LIKE '.1%';
} {.1%}


# 2019-02-27
# Verify that the LIKE optimization works with an ESCAPE clause when
# using PRAGMA case_sensitive_like=ON.
#
ifcapable !icu {

Changes to test/tkt-78e04e52ea.test.

37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
} {0 {} {} 0 {} 0 1 x CHAR(100) 0 {} 0}
do_test tkt-78e04-1.3 {
  execsql {
    CREATE INDEX i1 ON ""("" COLLATE nocase);
  }
} {}
do_test tkt-78e04-1.4 {
 db eval {EXPLAIN QUERY PLAN SELECT "" FROM "" WHERE "" LIKE '1abc%';}
} {/*SCAN TABLE  USING COVERING INDEX i1*/}
do_test tkt-78e04-1.5 {
  execsql {
    DROP TABLE "";
    SELECT name FROM sqlite_master;
  }
} {t2}







|







37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
} {0 {} {} 0 {} 0 1 x CHAR(100) 0 {} 0}
do_test tkt-78e04-1.3 {
  execsql {
    CREATE INDEX i1 ON ""("" COLLATE nocase);
  }
} {}
do_test tkt-78e04-1.4 {
 db eval {EXPLAIN QUERY PLAN SELECT "" FROM "" WHERE "" LIKE '1e5%';}
} {/*SCAN TABLE  USING COVERING INDEX i1*/}
do_test tkt-78e04-1.5 {
  execsql {
    DROP TABLE "";
    SELECT name FROM sqlite_master;
  }
} {t2}

Changes to test/vtab1.test.

1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317



1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330



1331
1332
1333
1334
1335
1336
1337
  1.1 "SELECT a FROM e6 WHERE b>'8James'" {4 2 6 1 5}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b > ?} 8James}

  1.2 "SELECT a FROM e6 WHERE b>='8' AND b<'9'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ?} 8 9}

  1.3 "SELECT a FROM e6 WHERE b LIKE '8J%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8J%}

  1.4 "SELECT a FROM e6 WHERE b LIKE '8j%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8j%}



} {
  set echo_module {}
  do_execsql_test 18.$tn.1 $sql $res
  do_test         18.$tn.2 { lrange $::echo_module 2 end } $filter
}

do_execsql_test 18.2.0 {  PRAGMA case_sensitive_like = ON }
foreach {tn sql res filter} {
  2.1 "SELECT a FROM e6 WHERE b LIKE '8J%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8J%}

  2.2 "SELECT a FROM e6 WHERE b LIKE '8j%'" {}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8j%}



} {
  set echo_module {}
  do_execsql_test 18.$tn.1 $sql $res
  do_test         18.$tn.2 { lrange $::echo_module 2 end } $filter
}
do_execsql_test 18.2.x {  PRAGMA case_sensitive_like = OFF }








|


|
>
>
>








|
|


|
>
>
>







1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
  1.1 "SELECT a FROM e6 WHERE b>'8James'" {4 2 6 1 5}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b > ?} 8James}

  1.2 "SELECT a FROM e6 WHERE b>='8' AND b<'9'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ?} 8 9}

  1.3 "SELECT a FROM e6 WHERE b LIKE '8J%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b like ?} 8J 8k 8J%}

  1.4 "SELECT a FROM e6 WHERE b LIKE '8j%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b like ?} 8J 8k 8j%}

  1.5 "SELECT a FROM e6 WHERE b LIKE '8%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8%}
} {
  set echo_module {}
  do_execsql_test 18.$tn.1 $sql $res
  do_test         18.$tn.2 { lrange $::echo_module 2 end } $filter
}

do_execsql_test 18.2.0 {  PRAGMA case_sensitive_like = ON }
foreach {tn sql res filter} {
  2.1 "SELECT a FROM e6 WHERE b LIKE '8%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8%}

  2.2 "SELECT a FROM e6 WHERE b LIKE '8j%'" {}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b like ?} 8j 8k 8j%}

  2.3 "SELECT a FROM e6 WHERE b LIKE '8J%'" {3 4}
    {xFilter {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b like ?} 8J 8K 8J%}
} {
  set echo_module {}
  do_execsql_test 18.$tn.1 $sql $res
  do_test         18.$tn.2 { lrange $::echo_module 2 end } $filter
}
do_execsql_test 18.2.x {  PRAGMA case_sensitive_like = OFF }

Changes to test/vtabH.test.

28
29
30
31
32
33
34

35

36

37
38
39











40
41
42
43
44
45
46
47
48
  CREATE TABLE t6(a, b TEXT);
  CREATE INDEX i6 ON t6(b, a);
  CREATE VIRTUAL TABLE e6 USING echo(t6);
}

foreach {tn sql expect} {
  1 "SELECT * FROM e6 WHERE b LIKE '8abc'" {

    xBestIndex {SELECT rowid, a, b FROM 't6' WHERE b like ?}

    xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8abc

  }

  2 "SELECT * FROM e6 WHERE b GLOB '8abc'" {











    xBestIndex {SELECT rowid, a, b FROM 't6' WHERE b glob ?}
    xFilter {SELECT rowid, a, b FROM 't6' WHERE b glob ?} 8abc
  }
} {
  do_test 1.$tn {
    set echo_module {}
    execsql $sql
    set ::echo_module
  } [list {*}$expect]







>
|
>
|
>



>
>
>
>
>
>
>
>
>
>
>

|







28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
  CREATE TABLE t6(a, b TEXT);
  CREATE INDEX i6 ON t6(b, a);
  CREATE VIRTUAL TABLE e6 USING echo(t6);
}

foreach {tn sql expect} {
  1 "SELECT * FROM e6 WHERE b LIKE '8abc'" {
    xBestIndex 
       {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b like ?}
    xFilter
       {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b like ?}
       8ABC 8abd 8abc
  }

  2 "SELECT * FROM e6 WHERE b GLOB '8abc'" {
     xBestIndex
       {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b glob ?}
     xFilter
       {SELECT rowid, a, b FROM 't6' WHERE b >= ? AND b < ? AND b glob ?}
       8abc 8abd 8abc
  }
  3 "SELECT * FROM e6 WHERE b LIKE '8e/'" {
    xBestIndex {SELECT rowid, a, b FROM 't6' WHERE b like ?}
    xFilter {SELECT rowid, a, b FROM 't6' WHERE b like ?} 8e/
  }
  4 "SELECT * FROM e6 WHERE b GLOB '8e/'" {
    xBestIndex {SELECT rowid, a, b FROM 't6' WHERE b glob ?}
    xFilter {SELECT rowid, a, b FROM 't6' WHERE b glob ?} 8e/
  }
} {
  do_test 1.$tn {
    set echo_module {}
    execsql $sql
    set ::echo_module
  } [list {*}$expect]