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This document uses PHP Chinese website manual Release
(PHP 5 >= 5.3.11)
SQLite3::createCollation — Registers a PHP function for use as an SQL collating function
$name
, callable $callback
)Registers a PHP function or user-defined function for use as a collating function within SQL statements.
name
Name of the SQL collating function to be created or redefined
callback
The name of a PHP function or user-defined function to apply as a callback, defining the behavior of the collation. It should accept two strings and return as strcmp() does, i.e. it should return -1, 1, or 0 if the first string sorts before, sorts after, or is equal to the second.
成功时返回 TRUE
, 或者在失败时返回 FALSE
。
Example #1 SQLite3::createCollation() example
Register the PHP function strnatcmp() as a collating sequence in the SQLite3 database.
<?php
$db = new SQLite3 ( ":memory:" );
$db -> exec ( "CREATE TABLE test (col1 string)" );
$db -> exec ( "INSERT INTO test VALUES ('a1')" );
$db -> exec ( "INSERT INTO test VALUES ('a10')" );
$db -> exec ( "INSERT INTO test VALUES ('a2')" );
$db -> createCollation ( 'NATURAL_CMP' , 'strnatcmp' );
$defaultSort = $db -> query ( "SELECT col1 FROM test ORDER BY col1" );
$naturalSort = $db -> query ( "SELECT col1 FROM test ORDER BY col1 COLLATE NATURAL_CMP" );
echo "default:\n" ;
while ( $row = $defaultSort -> fetchArray ()){
echo $row [ 'col1' ], "\n" ;
}
echo "\nnatural:\n" ;
while ( $row = $naturalSort -> fetchArray ()){
echo $row [ 'col1' ], "\n" ;
}
$db -> close ();
?>
以上例程会输出:
default: a1 a10 a2natural: a1 a2 a10