1 # 2007 November 29

     2 #

     3 # The author disclaims copyright to this source code.  In place of

     4 # a legal notice, here is a blessing:

     5 #

     6 #    May you do good and not evil.

     7 #    May you find forgiveness for yourself and forgive others.

     8 #    May you share freely, never taking more than you give.

     9 #

    10 #***********************************************************************

    11 # This file tests the optimisations made in November 2007 of expressions 

    12 # of the following form:

    13 #

    14 #     <value> IN (SELECT <column> FROM <table>)

    15 #

    16 # $Id: in3.test,v 1.5 2008/08/04 03:51:24 danielk1977 Exp $

    17 

    18 set testdir [file dirname $argv0]

    19 source $testdir/tester.tcl

    20 

    21 ifcapable !subquery {

    22   finish_test

    23   return

    24 }

    25 

    26 # Return the number of OpenEphemeral instructions used in the

    27 # implementation of the sql statement passed as a an argument.

    28 #

    29 proc nEphemeral {sql} {

    30   set nEph 0

    31   foreach op [execsql "EXPLAIN $sql"] {

    32     if {$op eq "OpenEphemeral"} {incr nEph}

    33   }

    34   set nEph

    35 }

    36 

    37 # This proc works the same way as execsql, except that the number

    38 # of OpenEphemeral instructions used in the implementation of the

    39 # statement is inserted into the start of the returned list.

    40 #

    41 proc exec_neph {sql} {

    42   return [concat [nEphemeral $sql] [execsql $sql]]

    43 }

    44 

    45 do_test in3-1.1 {

    46   execsql {

    47     CREATE TABLE t1(a PRIMARY KEY, b);

    48     INSERT INTO t1 VALUES(1, 2);

    49     INSERT INTO t1 VALUES(3, 4);

    50     INSERT INTO t1 VALUES(5, 6);

    51   }

    52 } {}

    53 

    54 # All of these queries should avoid using a temp-table:

    55 #

    56 do_test in3-1.2 {

    57   exec_neph { SELECT rowid FROM t1 WHERE rowid IN (SELECT rowid FROM t1); }

    58 } {0 1 2 3}

    59 do_test in3-1.3 {

    60   exec_neph { SELECT a FROM t1 WHERE a IN (SELECT a FROM t1); }

    61 } {0 1 3 5}

    62 do_test in3-1.4 {

    63   exec_neph { SELECT rowid FROM t1 WHERE rowid+0 IN (SELECT rowid FROM t1); }

    64 } {0 1 2 3}

    65 do_test in3-1.5 {

    66   exec_neph { SELECT a FROM t1 WHERE a+0 IN (SELECT a FROM t1); }

    67 } {0 1 3 5}

    68 

    69 # Because none of the sub-select queries in the following statements

    70 # match the pattern ("SELECT <column> FROM <table>"), the following do 

    71 # require a temp table.

    72 #

    73 do_test in3-1.6 {

    74   exec_neph { SELECT rowid FROM t1 WHERE rowid IN (SELECT rowid+0 FROM t1); }

    75 } {1 1 2 3}

    76 do_test in3-1.7 {

    77   exec_neph { SELECT a FROM t1 WHERE a IN (SELECT a+0 FROM t1); }

    78 } {1 1 3 5}

    79 do_test in3-1.8 {

    80   exec_neph { SELECT a FROM t1 WHERE a IN (SELECT a FROM t1 WHERE 1); }

    81 } {1 1 3 5}

    82 do_test in3-1.9 {

    83   exec_neph { SELECT a FROM t1 WHERE a IN (SELECT a FROM t1 GROUP BY a); }

    84 } {1 1 3 5}

    85 

    86 # This should not use a temp-table. Even though the sub-select does

    87 # not exactly match the pattern "SELECT <column> FROM <table>", in

    88 # this case the ORDER BY is a no-op and can be ignored.

    89 do_test in3-1.10 {

    90   exec_neph { SELECT a FROM t1 WHERE a IN (SELECT a FROM t1 ORDER BY a); }

    91 } {0 1 3 5}

    92 

    93 # These do use the temp-table. Adding the LIMIT clause means the 

    94 # ORDER BY cannot be ignored.

    95 do_test in3-1.11 {

    96   exec_neph {SELECT a FROM t1 WHERE a IN (SELECT a FROM t1 ORDER BY a LIMIT 1)}

    97 } {1 1}

    98 do_test in3-1.12 {

    99   exec_neph {

   100     SELECT a FROM t1 WHERE a IN (SELECT a FROM t1 ORDER BY a LIMIT 1 OFFSET 1)

   101   }

   102 } {1 3}

   103 

   104 # Has to use a temp-table because of the compound sub-select.

   105 #

   106 ifcapable compound {

   107   do_test in3-1.13 {

   108     exec_neph {

   109       SELECT a FROM t1 WHERE a IN (

   110         SELECT a FROM t1 UNION ALL SELECT a FROM t1

   111       )

   112     }

   113   } {1 1 3 5}

   114 }

   115 

   116 # The first of these queries has to use the temp-table, because the 

   117 # collation sequence used for the index on "t1.a" does not match the

   118 # collation sequence used by the "IN" comparison. The second does not

   119 # require a temp-table, because the collation sequences match.

   120 #

   121 do_test in3-1.14 {

   122   exec_neph { SELECT a FROM t1 WHERE a COLLATE nocase IN (SELECT a FROM t1) }

   123 } {1 1 3 5}

   124 do_test in3-1.15 {

   125   exec_neph { SELECT a FROM t1 WHERE a COLLATE binary IN (SELECT a FROM t1) }

   126 } {0 1 3 5}

   127 

   128 # Neither of these queries require a temp-table. The collation sequence

   129 # makes no difference when using a rowid.

   130 #

   131 do_test in3-1.16 {

   132   exec_neph {SELECT a FROM t1 WHERE a COLLATE nocase IN (SELECT rowid FROM t1)}

   133 } {0 1 3}

   134 do_test in3-1.17 {

   135   exec_neph {SELECT a FROM t1 WHERE a COLLATE binary IN (SELECT rowid FROM t1)}

   136 } {0 1 3}

   137 

   138 # The following tests - in3.2.* - test a bug that was difficult to track

   139 # down during development. They are not particularly well focused.

   140 #

   141 do_test in3-2.1 {

   142   execsql {

   143     DROP TABLE IF EXISTS t1;

   144     CREATE TABLE t1(w int, x int, y int);

   145     CREATE TABLE t2(p int, q int, r int, s int);

   146   }

   147   for {set i 1} {$i<=100} {incr i} {

   148     set w $i

   149     set x [expr {int(log($i)/log(2))}]

   150     set y [expr {$i*$i + 2*$i + 1}]

   151     execsql "INSERT INTO t1 VALUES($w,$x,$y)"

   152   }

   153   set maxy [execsql {select max(y) from t1}]

   154   db eval { INSERT INTO t2 SELECT 101-w, x, $maxy+1-y, y FROM t1 }

   155 } {}

   156 do_test in3-2.2 {

   157   execsql {

   158     SELECT rowid 

   159     FROM t1 

   160     WHERE rowid IN (SELECT rowid FROM t1 WHERE rowid IN (1, 2));

   161   }

   162 } {1 2}

   163 do_test in3-2.3 {

   164   execsql {

   165     select rowid from t1 where rowid IN (-1,2,4)

   166   }

   167 } {2 4}

   168 do_test in3-2.4 {

   169   execsql {

   170     SELECT rowid FROM t1 WHERE rowid IN 

   171        (select rowid from t1 where rowid IN (-1,2,4))

   172   }

   173 } {2 4}

   174 

   175 #-------------------------------------------------------------------------

   176 # This next block of tests - in3-3.* - verify that column affinity is

   177 # correctly handled in cases where an index might be used to optimise

   178 # an IN (SELECT) expression.

   179 #

   180 do_test in3-3.1 {

   181   catch {execsql {

   182     DROP TABLE t1;

   183     DROP TABLE t2;

   184   }}

   185 

   186   execsql {

   187 

   188     CREATE TABLE t1(a BLOB, b NUMBER ,c TEXT);

   189     CREATE UNIQUE INDEX t1_i1 ON t1(a);        /* no affinity */

   190     CREATE UNIQUE INDEX t1_i2 ON t1(b);        /* numeric affinity */

   191     CREATE UNIQUE INDEX t1_i3 ON t1(c);        /* text affinity */

   192 

   193     CREATE TABLE t2(x BLOB, y NUMBER, z TEXT);

   194     CREATE UNIQUE INDEX t2_i1 ON t2(x);        /* no affinity */

   195     CREATE UNIQUE INDEX t2_i2 ON t2(y);        /* numeric affinity */

   196     CREATE UNIQUE INDEX t2_i3 ON t2(z);        /* text affinity */

   197 

   198     INSERT INTO t1 VALUES(1, 1, 1);

   199     INSERT INTO t2 VALUES('1', '1', '1');

   200   }

   201 } {}

   202 

   203 do_test in3-3.2 {

   204   # No affinity is applied before comparing "x" and "a". Therefore

   205   # the index can be used (the comparison is false, text!=number).

   206   exec_neph { SELECT x IN (SELECT a FROM t1) FROM t2 }

   207 } {0 0}

   208 do_test in3-3.3 {

   209   # Logically, numeric affinity is applied to both sides before 

   210   # the comparison.  Therefore it is possible to use index t1_i2.

   211   exec_neph { SELECT x IN (SELECT b FROM t1) FROM t2 }

   212 } {0 1}

   213 do_test in3-3.4 {

   214   # No affinity is applied before the comparison takes place. Making

   215   # it possible to use index t1_i3.

   216   exec_neph { SELECT x IN (SELECT c FROM t1) FROM t2 }

   217 } {0 1}

   218 

   219 do_test in3-3.5 {

   220   # Numeric affinity should be applied to each side before the comparison

   221   # takes place. Therefore we cannot use index t1_i1, which has no affinity.

   222   exec_neph { SELECT y IN (SELECT a FROM t1) FROM t2 }

   223 } {1 1}

   224 do_test in3-3.6 {

   225   # Numeric affinity is applied to both sides before 

   226   # the comparison.  Therefore it is possible to use index t1_i2.

   227   exec_neph { SELECT y IN (SELECT b FROM t1) FROM t2 }

   228 } {0 1}

   229 do_test in3-3.7 {

   230   # Numeric affinity is applied before the comparison takes place. 

   231   # Making it impossible to use index t1_i3.

   232   exec_neph { SELECT y IN (SELECT c FROM t1) FROM t2 }

   233 } {1 1}

   234 

   235 #---------------------------------------------------------------------

   236 #

   237 # Test using a multi-column index.

   238 #

   239 do_test in3-4.1 {

   240   execsql {

   241     CREATE TABLE t3(a, b, c);

   242     CREATE UNIQUE INDEX t3_i ON t3(b, a);

   243   }

   244 

   245   execsql {

   246     INSERT INTO t3 VALUES(1, 'numeric', 2);

   247     INSERT INTO t3 VALUES(2, 'text', 2);

   248     INSERT INTO t3 VALUES(3, 'real', 2);

   249     INSERT INTO t3 VALUES(4, 'none', 2);

   250   }

   251 } {}

   252 do_test in3-4.2 {

   253   exec_neph { SELECT 'text' IN (SELECT b FROM t3) }

   254 } {0 1}

   255 do_test in3-4.3 {

   256   exec_neph { SELECT 'TEXT' COLLATE nocase IN (SELECT b FROM t3) }

   257 } {1 1}

   258 do_test in3-4.4 {

   259   # A temp table must be used because t3_i.b is not guaranteed to be unique.

   260   exec_neph { SELECT b FROM t3 WHERE b IN (SELECT b FROM t3) }

   261 } {1 none numeric real text}

   262 do_test in3-4.5 {

   263   execsql { CREATE UNIQUE INDEX t3_i2 ON t3(b) }

   264   exec_neph { SELECT b FROM t3 WHERE b IN (SELECT b FROM t3) }

   265 } {0 none numeric real text}

   266 do_test in3-4.6 {

   267   execsql { DROP INDEX t3_i2 }

   268 } {}

   269 

   270 # The following two test cases verify that ticket #2991 has been fixed.

   271 #

   272 do_test in3-5.1 {

   273   execsql {

   274     CREATE TABLE Folders(

   275       folderid INTEGER PRIMARY KEY, 

   276       parentid INTEGER, 

   277       rootid INTEGER, 

   278       path VARCHAR(255)

   279     );

   280   }

   281 } {}

   282 do_test in3-5.2 {

   283   catchsql {

   284     DELETE FROM Folders WHERE folderid IN

   285     (SELECT folderid FROM Folder WHERE path LIKE 'C:\MP3\Albums\' || '%');

   286   }

   287 } {1 {no such table: Folder}}

   288 

   289 finish_test