1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
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
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
# 2017 April 30
#
# 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.
#
#***********************************************************************
#
# Test the HAVING->WHERE optimization.
#
set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix having
do_execsql_test 1.0 {
CREATE TABLE t2(c, d);
CREATE TABLE t1(a, b);
INSERT INTO t1 VALUES(1, 1);
INSERT INTO t1 VALUES(2, 2);
INSERT INTO t1 VALUES(1, 3);
INSERT INTO t1 VALUES(2, 4);
INSERT INTO t1 VALUES(1, 5);
INSERT INTO t1 VALUES(2, 6);
} {}
foreach {tn sql res} {
1 "SELECT a, sum(b) FROM t1 GROUP BY a HAVING a=2" {2 12}
2 "SELECT a, sum(b) FROM t1 GROUP BY a HAVING a=2 AND sum(b)>10" {2 12}
3 "SELECT a, sum(b) FROM t1 GROUP BY a HAVING sum(b)>12" {}
} {
do_execsql_test 1.$tn $sql $res
}
# Run an EXPLAIN command for both SQL statements. Return true if
# the outputs are identical, or false otherwise.
#
proc compare_vdbe {sql1 sql2} {
set r1 [list]
set r2 [list]
db eval "explain $sql1" { lappend r1 $opcode $p1 $p2 $p3 $p4 $p5}
db eval "explain $sql2" { lappend r2 $opcode $p1 $p2 $p3 $p4 $p5}
return [expr {$r1==$r2}]
}
proc do_compare_vdbe_test {tn sql1 sql2 res} {
uplevel [list do_test $tn [list compare_vdbe $sql1 $sql2] $res]
}
#-------------------------------------------------------------------------
# Test that various statements that are eligible for the optimization
# produce the same VDBE code as optimizing by hand does.
#
foreach {tn sql1 sql2} {
1 "SELECT a, sum(b) FROM t1 GROUP BY a HAVING a=2"
"SELECT a, sum(b) FROM t1 WHERE a=2 GROUP BY a"
2 "SELECT a, sum(b) FROM t1 GROUP BY a HAVING sum(b)>5 AND a=2"
"SELECT a, sum(b) FROM t1 WHERE a=2 GROUP BY a HAVING sum(b)>5"
3 "SELECT a, sum(b) FROM t1 GROUP BY a COLLATE binary HAVING a=2"
"SELECT a, sum(b) FROM t1 WHERE a=2 GROUP BY a COLLATE binary"
5 "SELECT a, sum(b) FROM t1 GROUP BY a COLLATE binary HAVING 1"
"SELECT a, sum(b) FROM t1 WHERE 1 GROUP BY a COLLATE binary"
6 "SELECT count(*) FROM t1,t2 WHERE a=c GROUP BY b, d HAVING b=d"
"SELECT count(*) FROM t1,t2 WHERE a=c AND b=d GROUP BY b, d"
7 {
SELECT count(*) FROM t1,t2 WHERE a=c GROUP BY b, d
HAVING b=d COLLATE nocase
} {
SELECT count(*) FROM t1,t2 WHERE a=c AND b=d COLLATE nocase
GROUP BY b, d
}
8 "SELECT a, sum(b) FROM t1 GROUP BY a||b HAVING substr(a||b, 1, 1)='a'"
"SELECT a, sum(b) FROM t1 WHERE substr(a||b, 1, 1)='a' GROUP BY a||b"
} {
do_compare_vdbe_test 2.$tn $sql1 $sql2 1
}
# The (4) test in the above set used to generate identical bytecode, but
# that is no longer the case. The byte code is equivalent, though.
#
do_execsql_test 2.4a {
SELECT x,y FROM (
SELECT a AS x, sum(b) AS y FROM t1
GROUP BY a
) WHERE x BETWEEN 2 AND 9999
} {2 12}
do_execsql_test 2.4b {
SELECT x,y FROM (
SELECT a AS x, sum(b) AS y FROM t1
WHERE x BETWEEN 2 AND 9999
GROUP BY a
)
} {2 12}
#-------------------------------------------------------------------------
# 1: Test that the optimization is only applied if the GROUP BY term
# uses BINARY collation.
#
# 2: Not applied if there is a non-deterministic function in the HAVING
# term.
#
foreach {tn sql1 sql2} {
1 "SELECT a, sum(b) FROM t1 GROUP BY a COLLATE nocase HAVING a=2"
"SELECT a, sum(b) FROM t1 WHERE a=2 GROUP BY a COLLATE nocase"
2 "SELECT a, sum(b) FROM t1 GROUP BY a HAVING randomblob(a)<X'88'"
"SELECT a, sum(b) FROM t1 WHERE randomblob(a)<X'88' GROUP BY a"
} {
do_compare_vdbe_test 3.$tn $sql1 $sql2 0
}
#-------------------------------------------------------------------------
# Test that non-deterministic functions disqualify a term from being
# moved from the HAVING to WHERE clause.
#
do_execsql_test 4.1 {
CREATE TABLE t3(a, b);
INSERT INTO t3 VALUES(1, 1);
INSERT INTO t3 VALUES(1, 2);
INSERT INTO t3 VALUES(1, 3);
INSERT INTO t3 VALUES(2, 1);
INSERT INTO t3 VALUES(2, 2);
INSERT INTO t3 VALUES(2, 3);
}
proc nondeter {args} {
incr ::nondeter_ret
expr {$::nondeter_ret % 2}
}
db func nondeter nondeter
set ::nondeter_ret 0
do_execsql_test 4.2 {
SELECT a, sum(b) FROM t3 GROUP BY a HAVING nondeter(a)
} {1 6}
# If the term where moved, the query above would return the same
# result as the following. But it does not.
#
set ::nondeter_ret 0
do_execsql_test 4.3 {
SELECT a, sum(b) FROM t3 WHERE nondeter(a) GROUP BY a
} {1 4 2 2}
#-------------------------------------------------------------------------
reset_db
do_execsql_test 5.0 {
CREATE TABLE t1(a, b);
CREATE TABLE t2(x, y);
INSERT INTO t1 VALUES('a', 'b');
}
# The WHERE clause (a=2), uses an aggregate column from the outer query.
# If the HAVING term (0) is moved into the WHERE clause in this case,
# SQLite would at one point optimize (a=2 AND 0) to simply (0). Which
# is logically correct, but happened to cause problems in aggregate
# processing for the outer query. This test case verifies that those
# problems are no longer present.
do_execsql_test 5.1 {
SELECT min(b), (
SELECT x FROM t2 WHERE a=2 GROUP BY y HAVING 0
) FROM t1;
} {b {}}
# From chromium
# https://bugs.chromium.org/p/chromium/issues/detail?id=1161869
#
do_execsql_test 5.2 {
SELECT EXISTS (
SELECT * FROM (
SELECT * FROM (
SELECT 1
) WHERE Col0 = 1 GROUP BY 1
) WHERE 0
)
FROM (SELECT 1 Col0) GROUP BY 1
} {0}
finish_test
|
