| # 2011 August 13 |
| # |
| # 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 tests for SQLite library. The focus of the tests |
| # in this file is testing the capabilities of sqlite_stat3. |
| # |
| |
| set testdir [file dirname $argv0] |
| source $testdir/tester.tcl |
| |
| ifcapable !stat4&&!stat3 { |
| finish_test |
| return |
| } |
| |
| set testprefix analyze8 |
| |
| proc eqp {sql {db db}} { |
| uplevel execsql [list "EXPLAIN QUERY PLAN $sql"] $db |
| } |
| |
| # Scenario: |
| # |
| # Two indices. One has mostly singleton entries, but for a few |
| # values there are hundreds of entries. The other has 10-20 |
| # entries per value. |
| # |
| # Verify that the query planner chooses the first index for the singleton |
| # entries and the second index for the others. |
| # |
| do_test 1.0 { |
| db eval { |
| CREATE TABLE t1(a,b,c,d); |
| CREATE INDEX t1a ON t1(a); |
| CREATE INDEX t1b ON t1(b); |
| CREATE INDEX t1c ON t1(c); |
| } |
| for {set i 0} {$i<1000} {incr i} { |
| if {$i%2==0} {set a $i} {set a [expr {($i%8)*100}]} |
| set b [expr {$i/10}] |
| set c [expr {$i/8}] |
| set c [expr {$c*$c*$c}] |
| db eval {INSERT INTO t1 VALUES($a,$b,$c,$i)} |
| } |
| db eval {ANALYZE} |
| } {} |
| |
| # The a==100 comparison is expensive because there are many rows |
| # with a==100. And so for those cases, choose the t1b index. |
| # |
| # Buf ro a==99 and a==101, there are far fewer rows so choose |
| # the t1a index. |
| # |
| do_test 1.1 { |
| eqp {SELECT * FROM t1 WHERE a=100 AND b=55} |
| } {/*SEARCH TABLE t1 USING INDEX t1b (b=?)*/} |
| do_test 1.2 { |
| eqp {SELECT * FROM t1 WHERE a=99 AND b=55} |
| } {/*SEARCH TABLE t1 USING INDEX t1a (a=?)*/} |
| do_test 1.3 { |
| eqp {SELECT * FROM t1 WHERE a=101 AND b=55} |
| } {/*SEARCH TABLE t1 USING INDEX t1a (a=?)*/} |
| do_test 1.4 { |
| eqp {SELECT * FROM t1 WHERE a=100 AND b=56} |
| } {/*SEARCH TABLE t1 USING INDEX t1b (b=?)*/} |
| do_test 1.5 { |
| eqp {SELECT * FROM t1 WHERE a=99 AND b=56} |
| } {/*SEARCH TABLE t1 USING INDEX t1a (a=?)*/} |
| do_test 1.6 { |
| eqp {SELECT * FROM t1 WHERE a=101 AND b=56} |
| } {/*SEARCH TABLE t1 USING INDEX t1a (a=?)*/} |
| do_test 2.1 { |
| eqp {SELECT * FROM t1 WHERE a=100 AND b BETWEEN 50 AND 54} |
| } {/*SEARCH TABLE t1 USING INDEX t1b (b>? AND b<?)*/} |
| |
| # There are many more values of c between 0 and 100000 than there are |
| # between 800000 and 900000. So t1c is more selective for the latter |
| # range. |
| # |
| # Test 3.2 is a little unstable. It depends on the planner estimating |
| # that (b BETWEEN 30 AND 34) will match more rows than (c BETWEEN |
| # 800000 AND 900000). Which is a pretty close call (50 vs. 32), so |
| # the planner could get it wrong with an unlucky set of samples. This |
| # case happens to work, but others ("b BETWEEN 40 AND 44" for example) |
| # will fail. |
| # |
| do_execsql_test 3.0 { |
| SELECT count(*) FROM t1 WHERE b BETWEEN 30 AND 34; |
| SELECT count(*) FROM t1 WHERE c BETWEEN 0 AND 100000; |
| SELECT count(*) FROM t1 WHERE c BETWEEN 800000 AND 900000; |
| } {50 376 32} |
| do_test 3.1 { |
| eqp {SELECT * FROM t1 WHERE b BETWEEN 30 AND 34 AND c BETWEEN 0 AND 100000} |
| } {/*SEARCH TABLE t1 USING INDEX t1b (b>? AND b<?)*/} |
| do_test 3.2 { |
| eqp {SELECT * FROM t1 |
| WHERE b BETWEEN 30 AND 34 AND c BETWEEN 800000 AND 900000} |
| } {/*SEARCH TABLE t1 USING INDEX t1c (c>? AND c<?)*/} |
| do_test 3.3 { |
| eqp {SELECT * FROM t1 WHERE a=100 AND c BETWEEN 0 AND 100000} |
| } {/*SEARCH TABLE t1 USING INDEX t1a (a=?)*/} |
| do_test 3.4 { |
| eqp {SELECT * FROM t1 |
| WHERE a=100 AND c BETWEEN 800000 AND 900000} |
| } {/*SEARCH TABLE t1 USING INDEX t1c (c>? AND c<?)*/} |
| |
| finish_test |