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60 lines
1.6 KiB
Text
60 lines
1.6 KiB
Text
# 2009 March 28
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#
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# The author disclaims copyright to this source code. In place of
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# a legal notice, here is a blessing:
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#
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# May you do good and not evil.
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# May you find forgiveness for yourself and forgive others.
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# May you share freely, never taking more than you give.
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#
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#***********************************************************************
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#
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# Ticket #3757: The cost functions on the query optimizer for the
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# IN operator can be improved.
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#
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# $Id: tkt3757.test,v 1.1 2009/03/29 00:13:04 drh Exp $
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set testdir [file dirname $argv0]
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source $testdir/tester.tcl
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# Evaluate SQL. Return the result set followed by the
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# and the number of full-scan steps.
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#
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proc count_steps {sql} {
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set r [db eval $sql]
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lappend r scan [db status step] sort [db status sort]
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}
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# Construct tables
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#
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do_test tkt3757-1.1 {
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db eval {
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CREATE TABLE t1(x INTEGER, y INTEGER, z TEXT);
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CREATE INDEX t1i1 ON t1(y,z);
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INSERT INTO t1 VALUES(1,2,'three');
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CREATE TABLE t2(a INTEGER, b TEXT);
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INSERT INTO t2 VALUES(2, 'two');
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ANALYZE;
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SELECT * FROM sqlite_stat1 ORDER BY 1, 2;
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}
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} {t1 t1i1 {1 1 1} t2 {} 1}
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# Modify statistics in order to make the optimizer then that:
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#
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# (1) Table T1 has about 250K entries
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# (2) There are only about 5 distinct values of T1.
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#
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# Then run a query with "t1.y IN (SELECT ..)" in the WHERE clause.
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# Make sure the index is used.
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#
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do_test tkt3757-1.2 {
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db eval {
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DELETE FROM sqlite_stat1;
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INSERT INTO sqlite_stat1 VALUES('t1','t1i1','250000 50000 30');
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}
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count_steps {
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SELECT * FROM t1 WHERE y IN (SELECT a FROM t2)
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}
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} {1 2 three scan 0 sort 0}
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finish_test
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