带有表前缀的PDO

时间:2012-04-19 18:41:22

标签: php mysql pdo

我有以下的Model类,我的所有模型都扩展了。

class Model {
    [...]
    protected static $_query; // Query preparated

    public function prepare($query = null) {
        [...] // Connect to PDO, bla bla bla

        self::$_query = self::$link->prepare($query);
    }

    [...]

}

class Login extends Model {
    public function getUser($username = null) {
        self::prepare('SELECT * FROM usuarios WHERE usuario = :username LIMIT 1');
        self::bindValue('username', $username);

        return self::fetch();
    }
}

问题是,我需要在我的mysql中插入前缀,以避免表冲突,但不想编辑我的所有查询。

clientone_tablename
clienttwo_tablename
clientthree_tablename

如何执行此操作,在准备查询时解析并插入表前缀?

我没有尝试任何东西,因为我所知道的是,将我的自定义PDO扩展到PHP PDO类,现在不是很多..

我见过这个:PDO - Working with table prefixes。但是不要做得很好......

谢谢!

2 个答案:

答案 0 :(得分:1)

只需重写您的查询即可使用某个变量中找到的表前缀。解析表名的所有查询比实际值更麻烦。 (你真的想写一个SQL解析器吗?)

答案 1 :(得分:1)

所以我假设你只有一个MySQL数据库(你的webhost上的最小包)并且需要为你的每个客户存储一个系统的副本。

我的建议是,你创建了一组独立的表(对于每个客户端),但名称不重要,因为你在client表中查找了表名。

以下是我的例子:客户表应该存储自己的表的表名 (例如,users_tbl = clientone_users用于客户端ID:1)因此,稍后您可以只查询clients表并获取他/她的表名,然后使用该结果查询他/她的用户,新闻,页面和文件表。

# SQL: new table structure
-- store the names of the clients tables here
CREATE TABLE clients(
    id INT NOT NULL AUTO_INCREMENT,
    PRIMARY KEY(id),
    name VARCHAR(50),
    address VARCHAR(250),
    email VARCHAR(50),
    pass BLOB,
    /* table names*/
    users_tbl VARCHAR(70),
    news_tbl VARCHAR(70),
    pages_tbl VARCHAR(70),
    files_tbl VARCHAR(70)
) ENGINE = InnoDB;

# PHP: Some definitions for the table structure
$tbl_names = array("_users","_news","_pages","_files");
$tbl_fields = array();
$tbl_fields[0] = array("id INT","users_col1 VARCHAR(10)","users_col2 VARCHAR(20)");
$tbl_fields[1] = array("id INT","news_col1 DATE",...);
$tbl_fields[2] = array(...);
$tbl_fields[3] = array(...);
// refers to YOUR clients table field names (see above)
$clients_fields = array("users_tbl", "news_tbl", "pages_tbl", "files_tbl");

# PHP: Create a user and create the users database
function createUser($name, $address, $email, $pass, $salt) {
    global $db, $tbl_names, $tbl_fields;
    $success = false;
    if ($db->beginTransaction()) {
        $sql = "INSERT INTO clients(name, address, email, pass)
                     VALUES (?, ?, ?, AES_ENCRYPT(?, ?));"
        $query = $db->prepare($sql);
        $query->execute(array($name, $address, $email, $pass, $salt));
        if ($query->rowCount() == 1) { # if rowCount() doesn't work
            # get the client ID        # there are alternative ways
            $client_id = $db->lastInsertId();
            for ($i=0; $i<sizeof($tbl_names); $i++) {
                $client_tbl_name = $name . $tbl_names[$i];
                $sql = "CREATE TABLE " . $client_tbl_name . "("
                           . implode(',', $tbl_fields[$i]) . ");";
                if (!$db->query($sql)) {
                    $db->rollBack();
                    return false;
                } else {
                    $sql = "UPDATE clients SET ".clients_fields[$i]."=? "
                                       ."WHERE id=?;";
                    $query = $db->prepare($sql);
                    if (!$query->execute(
                            array($client_tbl_name, (int)$client_id)
                                         )) {
                        $db->rollBack();
                        return false;
                    }
                }
            }
            $db->commit();
            $success = true;
        }
        if (!$success) $db->rollBack();
    }
    return $success;
}

# PHP: Get the Client's table names
function getClientsTableNames($client_id) {
    $sql = "SELECT (users_tbl, news_tbl, pages_tbl, files_tbl)
              FROM clients WHERE id=?;";
    $query = $db->prepare($sql);
    if ($query->execute(array((int)$client_id)))
        return $query->fetchAll();
    else
        return null;
}

# PHP: Use the table name to query it
function getClientsTable($client_id, $table_no) {
    $table_names = getClientsTableNames($client_id);
    if ($table_names != null && isset($table_names[$table_no])) {
        $sql = "SELECT * FROM ".$table_names[$table_no].";";
        $query = $db->prepare($sql);
        if ($query->execute(array((int)$client_id)))
            return $query->fetchAll();
    }
    return null;
}