gitlab.com/CoiaPrant/sqlite3@v1.19.1/testdata/tcl/analyze4.test (about) 1 # 2011 January 04 2 # 3 # The author disclaims copyright to this source code. In place of 4 # a legal notice, here is a blessing: 5 # 6 # May you do good and not evil. 7 # May you find forgiveness for yourself and forgive others. 8 # May you share freely, never taking more than you give. 9 # 10 #*********************************************************************** 11 # 12 # This file implements regression tests for SQLite library. This file 13 # implements tests for ANALYZE to verify that multiple rows containing 14 # a NULL value count as distinct rows for the purposes of analyze 15 # statistics. 16 # 17 # Also include test cases for collating sequences on indices. 18 # 19 20 set testdir [file dirname $argv0] 21 source $testdir/tester.tcl 22 23 # If SQLITE_OMIT_ALTERTABLE is defined, omit this file. 24 ifcapable !altertable { 25 finish_test 26 return 27 } 28 29 do_test analyze4-1.0 { 30 db eval { 31 CREATE TABLE t1(a,b); 32 CREATE INDEX t1a ON t1(a); 33 CREATE INDEX t1b ON t1(b); 34 INSERT INTO t1 VALUES(1,NULL); 35 INSERT INTO t1 SELECT a+1, b FROM t1; 36 INSERT INTO t1 SELECT a+2, b FROM t1; 37 INSERT INTO t1 SELECT a+4, b FROM t1; 38 INSERT INTO t1 SELECT a+8, b FROM t1; 39 INSERT INTO t1 SELECT a+16, b FROM t1; 40 INSERT INTO t1 SELECT a+32, b FROM t1; 41 INSERT INTO t1 SELECT a+64, b FROM t1; 42 ANALYZE; 43 } 44 45 # Should choose the t1a index since it is more specific than t1b. 46 db eval {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=5 AND b IS NULL} 47 } {/*SEARCH t1 USING INDEX t1a (a=?)*/} 48 49 # Verify that the t1b index shows that it does not narrow down the 50 # search any at all. 51 # 52 do_test analyze4-1.1 { 53 db eval { 54 SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx; 55 } 56 } {t1a {128 1} t1b {128 128}} 57 58 # Change half of the b values from NULL to a constant. Verify 59 # that the number of rows selected in stat1 is half the total 60 # number of rows. 61 # 62 do_test analyze4-1.2 { 63 db eval { 64 UPDATE t1 SET b='x' WHERE a%2; 65 ANALYZE; 66 SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx; 67 } 68 } {t1a {128 1} t1b {128 64}} 69 70 # Change the t1.b values all back to NULL. Add columns t1.c and t1.d. 71 # Create a multi-column indices using t1.b and verify that ANALYZE 72 # processes them correctly. 73 # 74 do_test analyze4-1.3 { 75 db eval { 76 UPDATE t1 SET b=NULL; 77 ALTER TABLE t1 ADD COLUMN c; 78 ALTER TABLE t1 ADD COLUMN d; 79 UPDATE t1 SET c=a/4, d=a/2; 80 CREATE INDEX t1bcd ON t1(b,c,d); 81 CREATE INDEX t1cdb ON t1(c,d,b); 82 CREATE INDEX t1cbd ON t1(c,b,d); 83 ANALYZE; 84 SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx; 85 } 86 } {t1a {128 1} t1b {128 128} t1bcd {128 128 4 2} t1cbd {128 4 4 2} t1cdb {128 4 2 2}} 87 88 # Verify that collating sequences are taken into account when computing 89 # ANALYZE statistics. 90 # 91 do_test analyze4-2.0 { 92 db eval { 93 CREATE TABLE t2( 94 x INTEGER PRIMARY KEY, 95 a TEXT COLLATE nocase, 96 b TEXT COLLATE rtrim, 97 c TEXT COLLATE binary 98 ); 99 CREATE INDEX t2a ON t2(a); 100 CREATE INDEX t2b ON t2(b); 101 CREATE INDEX t2c ON t2(c); 102 CREATE INDEX t2c2 ON t2(c COLLATE nocase); 103 CREATE INDEX t2c3 ON t2(c COLLATE rtrim); 104 INSERT INTO t2 VALUES(1, 'abc', 'abc', 'abc'); 105 INSERT INTO t2 VALUES(2, 'abC', 'abC', 'abC'); 106 INSERT INTO t2 VALUES(3, 'abc ', 'abc ', 'abc '); 107 INSERT INTO t2 VALUES(4, 'abC ', 'abC ', 'abC '); 108 INSERT INTO t2 VALUES(5, 'aBc', 'aBc', 'aBc'); 109 INSERT INTO t2 VALUES(6, 'aBC', 'aBC', 'aBC'); 110 INSERT INTO t2 VALUES(7, 'aBc ', 'aBc ', 'aBc '); 111 INSERT INTO t2 VALUES(8, 'aBC ', 'aBC ', 'aBC '); 112 ANALYZE; 113 SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t2' ORDER BY idx; 114 } 115 } {t2a {8 4} t2b {8 2} t2c {8 1} t2c2 {8 4} t2c3 {8 2}} 116 117 finish_test