xref: /sqlite-3.40.0/test/whereF.test (revision 8dfde89b)
1# 2012 November 9
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#
12# Test cases for query planning decisions.
13
14
15#
16# The tests in this file demonstrate the behaviour of the query planner
17# in determining the order in which joined tables are scanned.
18#
19# Assume there are two tables being joined - t1 and t2. Each has a cost
20# if it is the outer loop, and a cost if it is the inner loop. As follows:
21#
22#   t1(outer) - cost of scanning t1 as the outer loop.
23#   t1(inner) - cost of scanning t1 as the inner loop.
24#   t2(outer) - cost of scanning t2 as the outer loop.
25#   t2(inner) - cost of scanning t2 as the inner loop.
26#
27# Depending on the order in which the planner nests the scans, the total
28# cost of the join query is one of:
29#
30#   t1(outer) * t2(inner)
31#   t2(outer) * t1(inner)
32#
33# The tests in this file attempt to verify that the planner nests joins in
34# the correct order when the following are true:
35#
36#   + (t1(outer) * t2(inner)) > (t1(inner) * t2(outer)
37#   +  t1(outer) < t2(outer)
38#
39# In other words, when the best overall query plan has t2 as the outer loop,
40# but when the outer loop is considered independent of the inner, t1 is the
41# most efficient choice.
42#
43# In order to make them more predictable, automatic indexes are turned off for
44# the tests in this file.
45#
46
47set testdir [file dirname $argv0]
48source $testdir/tester.tcl
49set testprefix whereF
50
51do_execsql_test 1.0 {
52  PRAGMA automatic_index = 0;
53  CREATE TABLE t1(a, b, c);
54  CREATE TABLE t2(d, e, f);
55  CREATE UNIQUE INDEX i1 ON t1(a);
56  CREATE UNIQUE INDEX i2 ON t2(d);
57} {}
58
59foreach {tn sql} {
60  1 "SELECT * FROM t1,           t2 WHERE t1.a=t2.e AND t2.d<t1.b AND t1.c!=10"
61  2 "SELECT * FROM t2,           t1 WHERE t1.a=t2.e AND t2.d<t1.b AND t1.c!=10"
62  3 "SELECT * FROM t2 CROSS JOIN t1 WHERE t1.a=t2.e AND t2.d<t1.b AND t1.c!=10"
63} {
64  do_test 1.$tn {
65    db eval "EXPLAIN QUERY PLAN $sql"
66   } {/.*SCAN TABLE t2\y.*SEARCH TABLE t1\y.*/}
67}
68
69do_execsql_test 2.0 {
70  DROP TABLE t1;
71  DROP TABLE t2;
72  CREATE TABLE t1(a, b, c);
73  CREATE TABLE t2(d, e, f);
74
75  CREATE UNIQUE INDEX i1 ON t1(a);
76  CREATE UNIQUE INDEX i2 ON t1(b);
77  CREATE UNIQUE INDEX i3 ON t2(d);
78} {}
79
80foreach {tn sql} {
81  1 "SELECT * FROM t1,           t2 WHERE t1.a>? AND t2.d>t1.c AND t1.b=t2.e"
82  2 "SELECT * FROM t2,           t1 WHERE t1.a>? AND t2.d>t1.c AND t1.b=t2.e"
83  3 "SELECT * FROM t2 CROSS JOIN t1 WHERE t1.a>? AND t2.d>t1.c AND t1.b=t2.e"
84} {
85  do_test 2.$tn {
86    db eval "EXPLAIN QUERY PLAN $sql"
87   } {/.*SCAN TABLE t2\y.*SEARCH TABLE t1\y.*/}
88}
89
90do_execsql_test 3.0 {
91  DROP TABLE t1;
92  DROP TABLE t2;
93  CREATE TABLE t1(a, b, c);
94  CREATE TABLE t2(d, e, f);
95
96  CREATE UNIQUE INDEX i1 ON t1(a, b);
97  CREATE INDEX i2 ON t2(d);
98} {}
99
100foreach {tn sql} {
101  1 {SELECT t1.a, t1.b, t2.d, t2.e FROM t1, t2
102     WHERE t2.d=t1.b AND t1.a=(t2.d+1) AND t1.b = (t2.e+1)}
103
104  2 {SELECT t1.a, t1.b, t2.d, t2.e FROM t2, t1
105     WHERE t2.d=t1.b AND t1.a=(t2.d+1) AND t1.b = (t2.e+1)}
106
107  3 {SELECT t1.a, t1.b, t2.d, t2.e FROM t2 CROSS JOIN t1
108     WHERE t2.d=t1.b AND t1.a=(t2.d+1) AND t1.b = (t2.e+1)}
109} {
110  do_test 3.$tn {
111    db eval "EXPLAIN QUERY PLAN $sql"
112   } {/.*SCAN TABLE t2\y.*SEARCH TABLE t1\y.*/}
113}
114
115do_execsql_test 4.0 {
116  CREATE TABLE t4(a,b,c,d,e, PRIMARY KEY(a,b,c));
117  CREATE INDEX t4adc ON t4(a,d,c);
118  CREATE UNIQUE INDEX t4aebc ON t4(a,e,b,c);
119  EXPLAIN QUERY PLAN SELECT rowid FROM t4 WHERE a=? AND b=?;
120} {/a=. AND b=./}
121
122#-------------------------------------------------------------------------
123# Test the following case:
124#
125#   ... FROM t1, t2 WHERE (
126#     t2.rowid = +t1.rowid OR (t2.f2 = t1.f1 AND t1.f1!=-1)
127#   )
128#
129# where there is an index on t2(f2). The planner should use "t1" as the
130# outer loop. The inner loop, on "t2", is an OR optimization. One pass
131# for:
132#
133#     t2.rowid = $1
134#
135# and another for:
136#
137#     t2.f2=$1 AND $1!=-1
138#
139# the test is to ensure that on the second pass, the ($1!=-1) condition
140# is tested before any seek operations are performed - i.e. outside of
141# the loop through the f2=$1 range of the t2(f2) index.
142#
143reset_db
144do_execsql_test 5.0 {
145  CREATE TABLE t1(f1);
146  CREATE TABLE t2(f2);
147  CREATE INDEX t2f ON t2(f2);
148
149  INSERT INTO t1 VALUES(-1);
150  INSERT INTO t1 VALUES(-1);
151  INSERT INTO t1 VALUES(-1);
152  INSERT INTO t1 VALUES(-1);
153
154  WITH w(i) AS (
155    SELECT 1 UNION ALL SELECT i+1 FROM w WHERE i<1000
156  )
157  INSERT INTO t2 SELECT -1 FROM w;
158}
159
160do_execsql_test 5.1 {
161  SELECT count(*) FROM t1, t2 WHERE t2.rowid = +t1.rowid
162} {4}
163do_test 5.2 { expr [db status vmstep]<200 } 1
164
165do_execsql_test 5.3 {
166  SELECT count(*) FROM t1, t2 WHERE (
167    t2.rowid = +t1.rowid OR t2.f2 = t1.f1
168  )
169} {4000}
170do_test 5.4 { expr [db status vmstep]>1000 } 1
171
172do_execsql_test 5.5 {
173  SELECT count(*) FROM t1, t2 WHERE (
174    t2.rowid = +t1.rowid OR (t2.f2 = t1.f1 AND t1.f1!=-1)
175  )
176} {4}
177do_test 5.6 { expr [db status vmstep]<200 } 1
178
179# 2017-09-04 ticket b899b6042f97f52d
180# Segfault on correlated subquery...
181#
182ifcapable json1 {
183  do_execsql_test 6.1 {
184    CREATE TABLE t6(x);
185    SELECT * FROM t6 WHERE 1 IN (SELECT value FROM json_each(x));
186  } {}
187
188  do_execsql_test 6.2 {
189    DROP TABLE t6;
190    CREATE TABLE t6(a,b,c);
191    INSERT INTO t6 VALUES
192     (0,null,'{"a":0,"b":[3,4,5],"c":{"x":4.5,"y":7.8}}'),
193     (1,null,'{"a":1,"b":[3,4,5],"c":{"x":4.5,"y":7.8}}'),
194     (2,null,'{"a":9,"b":[3,4,5],"c":{"x":4.5,"y":7.8}}');
195    SELECT * FROM t6
196     WHERE (EXISTS (SELECT 1 FROM json_each(t6.c) AS x WHERE x.value=1));
197  } {1 {} {{"a":1,"b":[3,4,5],"c":{"x":4.5,"y":7.8}}}}
198
199}
200
201finish_test
202