# 2011 January 04

#

# 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. This file

# implements tests for ANALYZE to verify that multiple rows containing

# a NULL value count as distinct rows for the purposes of analyze

# statistics.

#

# Also include test cases for collating sequences on indices.

#

set testdir [file dirname $argv0]

source $testdir/tester.tcl

do_test analyze4-1.0 {

db eval {

CREATE TABLE t1(a,b);

CREATE INDEX t1a ON t1(a);

CREATE INDEX t1b ON t1(b);

INSERT INTO t1 VALUES(1,NULL);

INSERT INTO t1 SELECT a+1, b FROM t1;

INSERT INTO t1 SELECT a+2, b FROM t1;

INSERT INTO t1 SELECT a+4, b FROM t1;

INSERT INTO t1 SELECT a+8, b FROM t1;

INSERT INTO t1 SELECT a+16, b FROM t1;

INSERT INTO t1 SELECT a+32, b FROM t1;

INSERT INTO t1 SELECT a+64, b FROM t1;

ANALYZE;

}

# Should choose the t1a index since it is more specific than t1b.

db eval {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=5 AND b IS NULL}

} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?)}}

# Verify that the t1b index shows that it does not narrow down the

# search any at all.

#

do_test analyze4-1.1 {

db eval {

SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx;

}

} {t1a {128 1} t1b {128 128}}

# Change half of the b values from NULL to a constant. Verify

# that the number of rows selected in stat1 is half the total

# number of rows.

#

do_test analyze4-1.2 {

db eval {

UPDATE t1 SET b='x' WHERE a%2;

ANALYZE;

SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx;

}

} {t1a {128 1} t1b {128 64}}

# Change the t1.b values all back to NULL. Add columns t1.c and t1.d.

# Create a multi-column indices using t1.b and verify that ANALYZE

# processes them correctly.

#

do_test analyze4-1.3 {

db eval {

UPDATE t1 SET b=NULL;

ALTER TABLE t1 ADD COLUMN c;

ALTER TABLE t1 ADD COLUMN d;

UPDATE t1 SET c=a/4, d=a/2;

CREATE INDEX t1bcd ON t1(b,c,d);

CREATE INDEX t1cdb ON t1(c,d,b);

CREATE INDEX t1cbd ON t1(c,b,d);

ANALYZE;

SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t1' ORDER BY idx;

}

} {t1a {128 1} t1b {128 128} t1bcd {128 128 4 2} t1cbd {128 4 4 2} t1cdb {128 4 2 2}}

# Verify that collating sequences are taken into account when computing

# ANALYZE statistics.

#

do_test analyze4-2.0 {

db eval {

CREATE TABLE t2(

x INTEGER PRIMARY KEY,

a TEXT COLLATE nocase,

b TEXT COLLATE rtrim,

c TEXT COLLATE binary

);

CREATE INDEX t2a ON t2(a);

CREATE INDEX t2b ON t2(b);

CREATE INDEX t2c ON t2(c);

CREATE INDEX t2c2 ON t2(c COLLATE nocase);

CREATE INDEX t2c3 ON t2(c COLLATE rtrim);

INSERT INTO t2 VALUES(1, 'abc', 'abc', 'abc');

INSERT INTO t2 VALUES(2, 'abC', 'abC', 'abC');

INSERT INTO t2 VALUES(3, 'abc ', 'abc ', 'abc ');

INSERT INTO t2 VALUES(4, 'abC ', 'abC ', 'abC ');

INSERT INTO t2 VALUES(5, 'aBc', 'aBc', 'aBc');

INSERT INTO t2 VALUES(6, 'aBC', 'aBC', 'aBC');

INSERT INTO t2 VALUES(7, 'aBc ', 'aBc ', 'aBc ');

INSERT INTO t2 VALUES(8, 'aBC ', 'aBC ', 'aBC ');

ANALYZE;

SELECT idx, stat FROM sqlite_stat1 WHERE tbl='t2' ORDER BY idx;

}

} {t2a {8 4} t2b {8 2} t2c {8 1} t2c2 {8 4} t2c3 {8 2}}

finish_test