| # 2013-11-27 |
| # |
| # 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 of the "skip-scan" query strategy. |
| # |
| # The test cases in this file are derived from the description of |
| # the skip-scan query strategy in the "optoverview.html" document. |
| # |
| |
| set testdir [file dirname $argv0] |
| source $testdir/tester.tcl |
| |
| do_execsql_test skipscan2-1.1 { |
| CREATE TABLE people( |
| name TEXT PRIMARY KEY, |
| role TEXT NOT NULL, |
| height INT NOT NULL, -- in cm |
| CHECK( role IN ('student','teacher') ) |
| ); |
| CREATE INDEX people_idx1 ON people(role, height); |
| } {} |
| do_execsql_test skipscan2-1.2 { |
| INSERT INTO people VALUES('Alice','student',156); |
| INSERT INTO people VALUES('Bob','student',161); |
| INSERT INTO people VALUES('Cindy','student',155); |
| INSERT INTO people VALUES('David','student',181); |
| INSERT INTO people VALUES('Emily','teacher',158); |
| INSERT INTO people VALUES('Fred','student',163); |
| INSERT INTO people VALUES('Ginny','student',169); |
| INSERT INTO people VALUES('Harold','student',172); |
| INSERT INTO people VALUES('Imma','student',179); |
| INSERT INTO people VALUES('Jack','student',181); |
| INSERT INTO people VALUES('Karen','student',163); |
| INSERT INTO people VALUES('Logan','student',177); |
| INSERT INTO people VALUES('Megan','teacher',159); |
| INSERT INTO people VALUES('Nathan','student',163); |
| INSERT INTO people VALUES('Olivia','student',161); |
| INSERT INTO people VALUES('Patrick','teacher',180); |
| INSERT INTO people VALUES('Quiana','student',182); |
| INSERT INTO people VALUES('Robert','student',159); |
| INSERT INTO people VALUES('Sally','student',166); |
| INSERT INTO people VALUES('Tom','student',171); |
| INSERT INTO people VALUES('Ursula','student',170); |
| INSERT INTO people VALUES('Vance','student',179); |
| INSERT INTO people VALUES('Willma','student',175); |
| INSERT INTO people VALUES('Xavier','teacher',185); |
| INSERT INTO people VALUES('Yvonne','student',149); |
| INSERT INTO people VALUES('Zach','student',170); |
| } |
| |
| # Without ANALYZE, a skip-scan is not used |
| # |
| do_execsql_test skipscan2-1.3 { |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-1.3eqp { |
| EXPLAIN QUERY PLAN |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {~/*INDEX people_idx1 */} |
| |
| # Now do an ANALYZE. A skip-scan can be used after ANALYZE. |
| # |
| do_execsql_test skipscan2-1.4 { |
| ANALYZE; |
| -- We do not have enough people above to actually force the use |
| -- of a skip-scan. So make a manual adjustment to the stat1 table |
| -- to make it seem like there are many more. |
| UPDATE sqlite_stat1 SET stat='10000 5000 20' WHERE idx='people_idx1'; |
| UPDATE sqlite_stat1 SET stat='10000 1' WHERE idx='sqlite_autoindex_people_1'; |
| ANALYZE sqlite_master; |
| } |
| db cache flush |
| do_execsql_test skipscan2-1.5 { |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-1.5eqp { |
| EXPLAIN QUERY PLAN |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {/*INDEX people_idx1 */} |
| |
| # Same answer with other formulations of the same query |
| # |
| do_execsql_test skipscan2-1.6 { |
| SELECT name FROM people |
| WHERE role IN (SELECT DISTINCT role FROM people) |
| AND height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-1.7 { |
| SELECT name FROM people WHERE role='teacher' AND height>=180 |
| UNION ALL |
| SELECT name FROM people WHERE role='student' AND height>=180 |
| ORDER BY 1; |
| } {David Jack Patrick Quiana Xavier} |
| |
| # Add 8 more people, bringing the total to 34. Then the number of |
| # duplicates in the left-column of the index will be 17 and |
| # skip-scan should not be used after an (unfudged) ANALYZE. |
| # |
| do_execsql_test skipscan2-1.8 { |
| INSERT INTO people VALUES('Angie','student',166); |
| INSERT INTO people VALUES('Brad','student',176); |
| INSERT INTO people VALUES('Claire','student',168); |
| INSERT INTO people VALUES('Donald','student',162); |
| INSERT INTO people VALUES('Elaine','student',177); |
| INSERT INTO people VALUES('Frazier','student',159); |
| INSERT INTO people VALUES('Grace','student',179); |
| INSERT INTO people VALUES('Horace','student',166); |
| ANALYZE; |
| SELECT stat FROM sqlite_stat1 WHERE idx='people_idx1'; |
| } {{34 17 2}} |
| db cache flush |
| do_execsql_test skipscan2-1.9 { |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-1.9eqp { |
| EXPLAIN QUERY PLAN |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {~/*INDEX people_idx1 */} |
| |
| # Add 2 more people, bringing the total to 36. Then the number of |
| # duplicates in the left-column of the index will be 18 and |
| # skip-scan will be used after an (unfudged) ANALYZE. |
| # |
| do_execsql_test skipscan2-1.10 { |
| INSERT INTO people VALUES('Ingrad','student',155); |
| INSERT INTO people VALUES('Jacob','student',179); |
| ANALYZE; |
| SELECT stat FROM sqlite_stat1 WHERE idx='people_idx1'; |
| } {{36 18 2}} |
| db cache flush |
| do_execsql_test skipscan2-1.11 { |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-1.11eqp { |
| EXPLAIN QUERY PLAN |
| SELECT name FROM people WHERE height>=180 ORDER BY +name; |
| } {/*INDEX people_idx1 */} |
| |
| |
| # Repeat using a WITHOUT ROWID table. |
| # |
| do_execsql_test skipscan2-2.1 { |
| CREATE TABLE peoplew( |
| name TEXT PRIMARY KEY, |
| role TEXT NOT NULL, |
| height INT NOT NULL, -- in cm |
| CHECK( role IN ('student','teacher') ) |
| ) WITHOUT ROWID; |
| CREATE INDEX peoplew_idx1 ON peoplew(role, height); |
| INSERT INTO peoplew(name,role,height) |
| SELECT name, role, height FROM people; |
| SELECT name FROM peoplew WHERE height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-2.2 { |
| SELECT name FROM peoplew |
| WHERE role IN (SELECT DISTINCT role FROM peoplew) |
| AND height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-2.2 { |
| SELECT name FROM peoplew WHERE role='teacher' AND height>=180 |
| UNION ALL |
| SELECT name FROM peoplew WHERE role='student' AND height>=180 |
| ORDER BY 1; |
| } {David Jack Patrick Quiana Xavier} |
| |
| # Now do an ANALYZE. A skip-scan can be used after ANALYZE. |
| # |
| do_execsql_test skipscan2-2.4 { |
| ANALYZE; |
| } |
| db cache flush |
| do_execsql_test skipscan2-2.5 { |
| SELECT name FROM peoplew WHERE height>=180 ORDER BY +name; |
| } {David Jack Patrick Quiana Xavier} |
| do_execsql_test skipscan2-2.5eqp { |
| EXPLAIN QUERY PLAN |
| SELECT name FROM peoplew WHERE height>=180 ORDER BY +name; |
| } {/*INDEX peoplew_idx1 */} |
| |
| # A skip-scan on a PK index of a WITHOUT ROWID table. |
| # |
| do_execsql_test skipscan2-3.1 { |
| CREATE TABLE t3(a, b, c, PRIMARY KEY(a, b)) WITHOUT ROWID; |
| } |
| do_test skipscan2-3.2 { |
| for {set i 0} {$i < 1000} {incr i} { |
| execsql { INSERT INTO t3 VALUES($i%2, $i, 'xyz') } |
| } |
| execsql { ANALYZE } |
| } {} |
| do_eqp_test skipscan2-3.3eqp { |
| SELECT * FROM t3 WHERE b=42; |
| } {SEARCH t3 USING PRIMARY KEY (ANY(a) AND b=?)} |
| |
| |
| |
| finish_test |