INSERT INTO `table` SET `column`=COMPRESS("abcd")
SELECT * FROM `table` WHERE UNCOMPRESS(`column`)="abcd"

INSERT INTO `table` SET `column`=COMPRESS("abcd")
SELECT * FROM `table` WHERE `column`=COMPRESS("abcd")

SELECT * FROM `table` WHERE `compressed` = compress('test')

SELECT uncompress(test) as test FROM `table` WHERE `compressed` = compress('test')

SELECT * FROM `table` WHERE UNCOMPRESS(`column`)="abcd"

`column`= COMPRESS("abcd")

<?php
/* Connect to an ODBC database using driver invocation */
$dsn = 'mysql:dbname=test;host=localhost';
$user = 'root';
$password = '';
 
try {
    $dbh = new PDO($dsn, $user, $password);
} catch (PDOException $e) {
    echo 'Connection failed: ' . $e->getMessage();
}
 
$sql = 'SELECT binary(compressed) AS compressed FROM `compressed` WHERE compress(:test) = compressed ';
$sth = $dbh->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));
$sth->execute(array(':test' => 'test'));
$row = $sth->fetch();
 
// compressed result, with first 4 bytes being the length
$result = $row['compressed'];
 
// the length of uncompressed string
$len = substr($result, 0, 4);
// the compressed string
$compressed = substr($result, 4, strlen($result)-4);
 
// uncompress the string
echo gzuncompress($compressed, intval($len)); // test
 
?>

+------------+------+------+-----+---------+-------+
| Field      | Type | Null | Key | Default | Extra |
+------------+------+------+-----+---------+-------+
| value      | text | NO   |     | NULL    |       |
| compressed | blob | NO   |     | NULL    |       |
+------------+------+------+-----+---------+-------+

--
-- Database: `test`
--
 
-- --------------------------------------------------------
 
--
-- Table structure for table `compressed`
--
 
CREATE TABLE IF NOT EXISTS `compressed` (
  `value` text COLLATE utf8_unicode_ci NOT NULL,
  `compressed` blob NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
 
--
-- Dumping data for table `compressed`
--
 
INSERT INTO `compressed` (`value`, `compressed`) VALUES
('test', 0x04000000789c2b492d2e0100045d01c1);