like.test

sqlite-3.4.1,嵌入式数据库.是一个功能强大的开源数据库,给学习和研发以及小型公司的发展带来了全所未有的好处.

# 2005 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 regression tests for SQLite library.  The
# focus of this file is testing the LIKE and GLOB operators and
# in particular the optimizations that occur to help those operators
# run faster.
#
# $Id: like.test,v 1.6 2007/06/11 12:56:15 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Create some sample data to work with.
#
do_test like-1.0 {
  execsql {
    CREATE TABLE t1(x TEXT);
  }
  foreach str {
    a
    ab
    abc
    abcd

    acd
    abd
    bc
    bcd

    xyz
    ABC
    CDE
    {ABC abc xyz}
  } {
    db eval {INSERT INTO t1 VALUES(:str)}
  }
  execsql {
    SELECT count(*) FROM t1;
  }
} {12}

# Test that both case sensitive and insensitive version of LIKE work.
#
do_test like-1.1 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'abc' ORDER BY 1;
  }
} {ABC abc}
do_test like-1.2 {
  execsql {
    SELECT x FROM t1 WHERE x GLOB 'abc' ORDER BY 1;
  }
} {abc}
do_test like-1.3 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'ABC' ORDER BY 1;
  }
} {ABC abc}
do_test like-1.4 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'aBc' ORDER BY 1;
  }
} {ABC abc}
do_test like-1.5 {
  execsql {
    PRAGMA case_sensitive_like=on;
    SELECT x FROM t1 WHERE x LIKE 'abc' ORDER BY 1;
  }
} {abc}
do_test like-1.6 {
  execsql {
    SELECT x FROM t1 WHERE x GLOB 'abc' ORDER BY 1;
  }
} {abc}
do_test like-1.7 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'ABC' ORDER BY 1;
  }
} {ABC}
do_test like-1.8 {
  execsql {
    SELECT x FROM t1 WHERE x LIKE 'aBc' ORDER BY 1;
  }
} {}
do_test like-1.9 {
  execsql {
    PRAGMA case_sensitive_like=off;
    SELECT x FROM t1 WHERE x LIKE 'abc' ORDER BY 1;
  }
} {ABC abc}

# Tests of the REGEXP operator
#
do_test like-2.1 {
  proc test_regexp {a b} {
    return [regexp $a $b]
  }
  db function regexp test_regexp
  execsql {
    SELECT x FROM t1 WHERE x REGEXP 'abc' ORDER BY 1;
  }
} {{ABC abc xyz} abc abcd}
do_test like-2.2 {
  execsql {
    SELECT x FROM t1 WHERE x REGEXP '^abc' ORDER BY 1;
  }
} {abc abcd}

# Tests of the MATCH operator
#
do_test like-2.3 {
  proc test_match {a b} {
    return [string match $a $b]
  }
  db function match test_match
  execsql {
    SELECT x FROM t1 WHERE x MATCH '*abc*' ORDER BY 1;
  }
} {{ABC abc xyz} abc abcd}
do_test like-2.4 {
  execsql {
    SELECT x FROM t1 WHERE x MATCH 'abc*' ORDER BY 1;
  }
} {abc abcd}

# For the remaining tests, we need to have the like optimizations
# enabled.
#
ifcapable !like_opt {
  finish_test
  return
} 

# This procedure executes the SQL.  Then it appends to the result the
# "sort" or "nosort" keyword (as in the cksort procedure above) then
# it appends the ::sqlite_query_plan variable.
#
proc queryplan {sql} {
  set ::sqlite_sort_count 0
  set data [execsql $sql]
  if {$::sqlite_sort_count} {set x sort} {set x nosort}
  lappend data $x
  return [concat $data $::sqlite_query_plan]
}

# Perform tests on the like optimization.
#
# With no index on t1.x and with case sensitivity turned off, no optimization
# is performed.
#
do_test like-3.1 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {ABC {ABC abc xyz} abc abcd sort t1 {}}
do_test like-3.2 {
  set sqlite_like_count
} {12}

# With an index on t1.x and case sensitivity on, optimize completely.
#
do_test like-3.3 {
  set sqlite_like_count 0
  execsql {
    PRAGMA case_sensitive_like=on;
    CREATE INDEX i1 ON t1(x);
  }
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.4 {
  set sqlite_like_count
} 0

# Partial optimization when the pattern does not end in '%'
#
do_test like-3.5 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'a_c' ORDER BY 1;
  }
} {abc nosort {} i1}
do_test like-3.6 {
  set sqlite_like_count
} 6
do_test like-3.7 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'ab%d' ORDER BY 1;
  }
} {abcd abd nosort {} i1}
do_test like-3.8 {
  set sqlite_like_count
} 4
do_test like-3.9 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'a_c%' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.10 {
  set sqlite_like_count
} 6

# No optimization when the pattern begins with a wildcard.
# Note that the index is still used but only for sorting.
#
do_test like-3.11 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE '%bcd' ORDER BY 1;
  }
} {abcd bcd nosort {} i1}
do_test like-3.12 {
  set sqlite_like_count
} 12

# No optimization for case insensitive LIKE
#
do_test like-3.13 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=off;
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {ABC {ABC abc xyz} abc abcd nosort {} i1}
do_test like-3.14 {
  set sqlite_like_count
} 12

# No optimization without an index.
#
do_test like-3.15 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=on;
    DROP INDEX i1;
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1;
  }
} {abc abcd sort t1 {}}
do_test like-3.16 {
  set sqlite_like_count
} 12

# No GLOB optimization without an index.
#
do_test like-3.17 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x GLOB 'abc*' ORDER BY 1;
  }
} {abc abcd sort t1 {}}
do_test like-3.18 {
  set sqlite_like_count
} 12

# GLOB is optimized regardless of the case_sensitive_like setting.
#
do_test like-3.19 {
  set sqlite_like_count 0
  queryplan {
    CREATE INDEX i1 ON t1(x);
    SELECT x FROM t1 WHERE x GLOB 'abc*' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.20 {
  set sqlite_like_count
} 0
do_test like-3.21 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=on;
    SELECT x FROM t1 WHERE x GLOB 'abc*' ORDER BY 1;
  }
} {abc abcd nosort {} i1}
do_test like-3.22 {
  set sqlite_like_count
} 0
do_test like-3.23 {
  set sqlite_like_count 0
  queryplan {
    PRAGMA case_sensitive_like=off;
    SELECT x FROM t1 WHERE x GLOB 'a[bc]d' ORDER BY 1;
  }
} {abd acd nosort {} i1}
do_test like-3.24 {
  set sqlite_like_count
} 6

# No optimization if the LHS of the LIKE is not a column name or
# if the RHS is not a string.
#
do_test like-4.1 {
  execsql {PRAGMA case_sensitive_like=on}
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1
  }
} {abc abcd nosort {} i1}
do_test like-4.2 {
  set sqlite_like_count
} 0
do_test like-4.3 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE +x LIKE 'abc%' ORDER BY 1
  }
} {abc abcd nosort {} i1}
do_test like-4.4 {
  set sqlite_like_count
} 12
do_test like-4.5 {
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE ('ab' || 'c%') ORDER BY 1
  }
} {abc abcd nosort {} i1}
do_test like-4.6 {
  set sqlite_like_count
} 12

# Collating sequences on the index disable the LIKE optimization.
# Or if the NOCASE collating sequence is used, the LIKE optimization
# is enabled when case_sensitive_like is OFF.
#
do_test like-5.1 {
  execsql {PRAGMA case_sensitive_like=off}
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t1 WHERE x LIKE 'abc%' ORDER BY 1
  }
} {ABC {ABC abc xyz} abc abcd nosort {} i1}
do_test like-5.2 {
  set sqlite_like_count
} 12
do_test like-5.3 {
  execsql {
    CREATE TABLE t2(x COLLATE NOCASE);
    INSERT INTO t2 SELECT * FROM t1;
    CREATE INDEX i2 ON t2(x COLLATE NOCASE);
  }
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t2 WHERE x LIKE 'abc%' ORDER BY 1
  }
} {abc ABC {ABC abc xyz} abcd nosort {} i2}
do_test like-5.4 {
  set sqlite_like_count
} 0
do_test like-5.5 {
  execsql {
    PRAGMA case_sensitive_like=on;
  }
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t2 WHERE x LIKE 'abc%' ORDER BY 1
  }
} {abc abcd nosort {} i2}
do_test like-5.6 {
  set sqlite_like_count
} 12
do_test like-5.7 {
  execsql {
    PRAGMA case_sensitive_like=off;
  }
  set sqlite_like_count 0
  queryplan {
    SELECT x FROM t2 WHERE x GLOB 'abc*' ORDER BY 1
  }
} {abc abcd nosort {} i2}
do_test like-5.8 {
  set sqlite_like_count
} 12

# ticket #2407
#
# Make sure the LIKE prefix optimization does not strip off leading
# characters of the like pattern that happen to be quote characters.
#
do_test like-6.1 {
  foreach x { 'abc 'bcd 'def 'ax } {
    db eval {INSERT INTO t2 VALUES($x)}
  }
  execsql {
    SELECT * FROM t2 WHERE x LIKE '''a%'
  }
} {'abc 'ax}

finish_test