A script to change all tables and fields to the utf-8-bin collation in MYSQL

Question

Is there a SQL or PHP script that I can run that will change the default collation in all tables and fields in a database?

I can write one

Answer 1

I updated nlaq's answer to work with PHP7 and to correctly handle multicolumn indices, binary collated data (e.g. latin1_bin), etc., and cleaned up the code a bit. This is the only code I found/tried that successfully migrated my database from latin1 to utf8.

Mysql Error: " . mysqli_error($conn) . "\n";
        echo "This query caused the above error: " . $query . "\n";
    }
    return $res;
}

function binary_typename($type) {
    $mysql_type_to_binary_type_map = array(
        "VARCHAR" => "VARBINARY",
        "CHAR" => "BINARY(1)",
        "TINYTEXT" => "TINYBLOB",
        "MEDIUMTEXT" => "MEDIUMBLOB",
        "LONGTEXT" => "LONGBLOB",
        "TEXT" => "BLOB"
    );

    $typename = "";
    if (preg_match("/^varchar\((\d+)\)$/i", $type, $mat))
        $typename = $mysql_type_to_binary_type_map["VARCHAR"] . "(" . (2*$mat[1]) . ")";
    else if (!strcasecmp($type, "CHAR"))
        $typename = $mysql_type_to_binary_type_map["CHAR"] . "(1)";
    else if (array_key_exists(strtoupper($type), $mysql_type_to_binary_type_map))
        $typename = $mysql_type_to_binary_type_map[strtoupper($type)];
    return $typename;
}

echo "
";

// Connect to database
$conn = mysqli_connect($host, $username, $password);
mysqli_select_db($conn, $db);

// Get list of tables
$tabs = array();
$query = "SHOW TABLES";
$res = MySQLSafeQuery($conn, $query);
while (($row = mysqli_fetch_row($res)) != null)
    $tabs[] = $row[0];

// Now fix tables
foreach ($tabs as $tab) {
    $res = MySQLSafeQuery($conn, "SHOW INDEX FROM `{$tab}`");
    $indicies = array();

    while (($row = mysqli_fetch_array($res)) != null) {
        if ($row[2] != "PRIMARY") {
            $append = true;
            foreach ($indicies as $index) {
                if ($index["name"] == $row[2]) {
                    $index["col"][] = $row[4];
                    $append = false;
                }
            }
            if($append)
                $indicies[] = array("name" => $row[2], "unique" => !($row[1] == "1"), "col" => array($row[4]));
        }
    }

    foreach ($indicies as $index) {
        MySQLSafeQuery($conn, "ALTER TABLE `{$tab}` DROP INDEX `{$index["name"]}`");
        echo "Dropped index {$index["name"]}. Unique: {$index["unique"]}\n";
    }

    $res = MySQLSafeQuery($conn, "SHOW FULL COLUMNS FROM `{$tab}`");
    while (($row = mysqli_fetch_array($res)) != null) {
        $name = $row[0];
        $type = $row[1];
        $current_collation = $row[2];
        $target_collation_bak = $target_collation;
        if(!strcasecmp($current_collation, "latin1_bin"))
            $target_collation = $target_bin_collation;
        $set = false;
        $binary_typename = binary_typename($type);
        if ($binary_typename != "") {
            MySQLSafeQuery($conn, "ALTER TABLE `{$tab}` MODIFY `{$name}` {$binary_typename}");
            MySQLSafeQuery($conn, "ALTER TABLE `{$tab}` MODIFY `{$name}` {$type} CHARACTER SET '{$target_charset}' COLLATE '{$target_collation}'");
            $set = true;
            echo "Altered field {$name} on {$tab} from type {$type}\n";
        }
        $target_collation = $target_collation_bak;
    }

    // Rebuild indicies
    foreach ($indicies as $index) {
         // Handle multi-column indices
         $joined_col_str = "";
         foreach ($index["col"] as $col)
             $joined_col_str = $joined_col_str . ", `" . $col . "`";
         $joined_col_str = substr($joined_col_str, 2);

         $query = "";
         if ($index["unique"])
             $query = "CREATE UNIQUE INDEX `{$index["name"]}` ON `{$tab}` ({$joined_col_str})";
         else
             $query = "CREATE INDEX `{$index["name"]}` ON `{$tab}` ({$joined_col_str})";
         MySQLSafeQuery($conn, $query);

        echo "Created index {$index["name"]} on {$tab}. Unique: {$index["unique"]}\n";
    }

    // Set default character set and collation for table
    MySQLSafeQuery($conn, "ALTER TABLE `{$tab}`  DEFAULT CHARACTER SET '{$target_charset}' COLLATE '{$target_collation}'");
}

// Set default character set and collation for database
MySQLSafeQuery($conn, "ALTER DATABASE `{$db}` DEFAULT CHARACTER SET '{$target_charset}' COLLATE '{$target_collation}'");

mysqli_close($conn);
echo "
";

?>