sqlite/test/where3.test
drh 61dfc31d80 Query optimizer enhancement: In "FROM a,b,c left join d" allow the C table
to be reordered with A and B.  This used to be the case but the capability
was removed by (3203) and (3052) in response to ticket #1652.  This change
restores the capability. (CVS 3529)

FossilOrigin-Name: 7393c81b8cb9d4344ae744de9eabcb3af64f1db8
2006-12-16 16:25:15 +00:00

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# 2006 January 31
#
# 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.
#
#***********************************************************************
# This file implements regression tests for SQLite library. The
# focus of this file is testing the join reordering optimization
# in cases that include a LEFT JOIN.
#
# $Id: where3.test,v 1.3 2006/12/16 16:25:17 drh Exp $
set testdir [file dirname $argv0]
source $testdir/tester.tcl
# The following is from ticket #1652.
#
# A comma join then a left outer join: A,B left join C.
# Arrange indices so that the B table is chosen to go first.
# Also put an index on C, but make sure that A is chosen before C.
#
do_test where3-1.1 {
execsql {
CREATE TABLE t1(a, b);
CREATE TABLE t2(p, q);
CREATE TABLE t3(x, y);
INSERT INTO t1 VALUES(111,'one');
INSERT INTO t1 VALUES(222,'two');
INSERT INTO t1 VALUES(333,'three');
INSERT INTO t2 VALUES(1,111);
INSERT INTO t2 VALUES(2,222);
INSERT INTO t2 VALUES(4,444);
CREATE INDEX t2i1 ON t2(p);
INSERT INTO t3 VALUES(999,'nine');
CREATE INDEX t3i1 ON t3(x);
SELECT * FROM t1, t2 LEFT JOIN t3 ON q=x WHERE p=2 AND a=q;
}
} {222 two 2 222 {} {}}
# Ticket #1830
#
# This is similar to the above but with the LEFT JOIN on the
# other side.
#
do_test where3-1.2 {
execsql {
CREATE TABLE parent1(parent1key, child1key, Child2key, child3key);
CREATE TABLE child1 ( child1key NVARCHAR, value NVARCHAR );
CREATE UNIQUE INDEX PKIDXChild1 ON child1 ( child1key );
CREATE TABLE child2 ( child2key NVARCHAR, value NVARCHAR );
INSERT INTO parent1(parent1key,child1key,child2key)
VALUES ( 1, 'C1.1', 'C2.1' );
INSERT INTO child1 ( child1key, value ) VALUES ( 'C1.1', 'Value for C1.1' );
INSERT INTO child2 ( child2key, value ) VALUES ( 'C2.1', 'Value for C2.1' );
INSERT INTO parent1 ( parent1key, child1key, child2key )
VALUES ( 2, 'C1.2', 'C2.2' );
INSERT INTO child2 ( child2key, value ) VALUES ( 'C2.2', 'Value for C2.2' );
INSERT INTO parent1 ( parent1key, child1key, child2key )
VALUES ( 3, 'C1.3', 'C2.3' );
INSERT INTO child1 ( child1key, value ) VALUES ( 'C1.3', 'Value for C1.3' );
INSERT INTO child2 ( child2key, value ) VALUES ( 'C2.3', 'Value for C2.3' );
SELECT parent1.parent1key, child1.value, child2.value
FROM parent1
LEFT OUTER JOIN child1 ON child1.child1key = parent1.child1key
INNER JOIN child2 ON child2.child2key = parent1.child2key;
}
} {1 {Value for C1.1} {Value for C2.1} 2 {} {Value for C2.2} 3 {Value for C1.3} {Value for C2.3}}
# This procedure executes the SQL. Then it appends
# the ::sqlite_query_plan variable.
#
proc queryplan {sql} {
set ::sqlite_sort_count 0
set data [execsql $sql]
return [concat $data $::sqlite_query_plan]
}
# If you have a from clause of the form: A B C left join D
# then make sure the query optimizer is able to reorder the
# A B C part anyway it wants.
#
# Following the fix to ticket #1652, there was a time when
# the C table would not reorder. So the following reorderings
# were possible:
#
# A B C left join D
# B A C left join D
#
# But these reorders were not allowed
#
# C A B left join D
# A C B left join D
# C B A left join D
# B C A left join D
#
# The following tests are here to verify that the latter four
# reorderings are allowed again.
#
do_test where3-2.1 {
execsql {
CREATE TABLE tA(apk integer primary key, ax);
CREATE TABLE tB(bpk integer primary key, bx);
CREATE TABLE tC(cpk integer primary key, cx);
CREATE TABLE tD(dpk integer primary key, dx);
}
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE cpk=bx AND bpk=ax
}
} {tA {} tB * tC * tD *}
do_test where3-2.2 {
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE cpk=bx AND apk=bx
}
} {tB {} tA * tC * tD *}
do_test where3-2.3 {
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE cpk=bx AND apk=bx
}
} {tB {} tA * tC * tD *}
do_test where3-2.4 {
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE apk=cx AND bpk=ax
}
} {tC {} tA * tB * tD *}
do_test where3-2.5 {
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE cpk=ax AND bpk=cx
}
} {tA {} tC * tB * tD *}
do_test where3-2.5 {
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE bpk=cx AND apk=bx
}
} {tC {} tB * tA * tD *}
do_test where3-2.6 {
queryplan {
SELECT * FROM tA, tB, tC LEFT JOIN tD ON dpk=cx
WHERE cpk=bx AND apk=cx
}
} {tB {} tC * tA * tD *}
finish_test