MySQL Functions (PDO_MYSQL)

简介

PDO_MYSQL is a driver that implements the PHP Data Objects (PDO) interface to enable access from PHP to MySQL databases.

As of PHP 5.2.1, PDO_MYSQL uses emulated prepares by default. Formerly, PDO_MYSQL defaulted to native prepared statement support present in MySQL 4.1 and higher, and emulated them for older versions of the mysql client libraries.

MySQL 8

When running a PHP version before 7.1.16, or PHP 7.2 before 7.2.4, set MySQL 8 Server's default password plugin to mysql_native_password or else you will see errors similar to The server requested authentication method unknown to the client [caching_sha2_password] even when caching_sha2_password is not used.

This is because MySQL 8 defaults to caching_sha2_password, a plugin that is not recognized by the older PHP (mysqlnd) releases. Instead, change it by setting default_authentication_plugin=mysql_native_password in my.cnf. The caching_sha2_password plugin will be supported in a future PHP release. In the meantime, the mysql_xdevapi extension does support it.

Warning

Beware: Some MySQL table types (storage engines) do not support transactions. When writing transactional database code using a table type that does not support transactions, MySQL will pretend that a transaction was initiated successfully. In addition, any DDL queries issued will implicitly commit any pending transactions.

安装

The common Unix distributions include binary versions of PHP that can be installed. Although these binary versions are typically built with support for the MySQL extensions, the extension libraries themselves may need to be installed using an additional package. Check the package manager than comes with your chosen distribution for availability.

For example, on Ubuntu the php5-mysql package installs the ext/mysql, ext/mysqli, and PDO_MYSQL PHP extensions. On CentOS, the php-mysql package also installs these three PHP extensions.

Alternatively, you can compile this extension yourself. Building PHP from source allows you to specify the MySQL extensions you want to use, as well as your choice of client library for each extension.

When compiling, use --with-pdo-mysql[=DIR] to install the PDO MySQL extension, where the optional [=DIR] is the MySQL base library. As of PHP 5.4, mysqlnd is the default library. For details about choosing a library, see Choosing a MySQL library.

Optionally, the --with-mysql-sock[=DIR] sets to location to the MySQL unix socket pointer for all MySQL extensions, including PDO_MYSQL. If unspecified, the default locations are searched.

Optionally, the --with-zlib-dir[=DIR] is used to set the path to the libz install prefix.

$ ./configure --with-pdo-mysql --with-mysql-sock=/var/mysql/mysql.sock

SSL support is enabled using the appropriate PDO_MySQL constants, which is equivalent to calling the » MySQL C API function mysql_ssl_set(). Also, SSL cannot be enabled with PDO::setAttribute because the connection already exists. See also the MySQL documentation about » connecting to MySQL with SSL.

更新日志
版本 说明
5.4.0 mysqlnd became the default MySQL library when compiling PDO_MYSQL. Previously, libmysqlclient was the default MySQL library.
5.4.0 MySQL client libraries 4.1 and below are no longer supported.
5.3.9 Added SSL support with mysqlnd and OpenSSL.
5.3.7 Added SSL support with libmysqlclient and OpenSSL.

预定义常量

下列常量由此驱动定义,且仅在扩展编译入 PHP 或在运行时动态载入时可用。另外,使用此驱动时,仅会使用这些驱动特定的常量。使用其他驱动的驱动特定的常量可能会导致不可预见的情况。如果代码可运行于多个驱动,PDO::getAttribute() 可被用于获取 PDO_ATTR_DRIVER_NAME 属性以检查驱动。

PDO::MYSQL_ATTR_USE_BUFFERED_QUERY (integer)
If this attribute is set to TRUE on a PDOStatement, the MySQL driver will use the buffered versions of the MySQL API. If you're writing portable code, you should use PDOStatement::fetchAll() instead.

Example #1 Forcing queries to be buffered in mysql

<?php
if ($db->getAttribute(PDO::ATTR_DRIVER_NAME) == 'mysql') {
    
$stmt $db->prepare('select * from foo',
        array(
PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => true));
} else {
    die(
"my application only works with mysql; I should use \$stmt->fetchAll() instead");
}
?>

PDO::MYSQL_ATTR_LOCAL_INFILE (integer)

Enable LOAD LOCAL INFILE.

Note, this constant can only be used in the driver_options array when constructing a new database handle.

PDO::MYSQL_ATTR_INIT_COMMAND (integer)

Command to execute when connecting to the MySQL server. Will automatically be re-executed when reconnecting.

Note, this constant can only be used in the driver_options array when constructing a new database handle.

PDO::MYSQL_ATTR_READ_DEFAULT_FILE (integer)

Read options from the named option file instead of from my.cnf. This option is not available if mysqlnd is used, because mysqlnd does not read the mysql configuration files.

PDO::MYSQL_ATTR_READ_DEFAULT_GROUP (integer)

Read options from the named group from my.cnf or the file specified with MYSQL_READ_DEFAULT_FILE. This option is not available if mysqlnd is used, because mysqlnd does not read the mysql configuration files.

PDO::MYSQL_ATTR_MAX_BUFFER_SIZE (integer)

Maximum buffer size. Defaults to 1 MiB. This constant is not supported when compiled against mysqlnd.

PDO::MYSQL_ATTR_DIRECT_QUERY (integer)

Perform direct queries, don't use prepared statements.

PDO::MYSQL_ATTR_FOUND_ROWS (integer)

Return the number of found (matched) rows, not the number of changed rows.

PDO::MYSQL_ATTR_IGNORE_SPACE (integer)

Permit spaces after function names. Makes all functions names reserved words.

PDO::MYSQL_ATTR_COMPRESS (integer)

Enable network communication compression. This is also supported when compiled against mysqlnd as of PHP 5.3.11.

PDO::MYSQL_ATTR_SSL_CA (integer)

The file path to the SSL certificate authority.

自以下版本起 PHP 5.3.7.

PDO::MYSQL_ATTR_SSL_CAPATH (integer)

The file path to the directory that contains the trusted SSL CA certificates, which are stored in PEM format.

自以下版本起 PHP 5.3.7.

PDO::MYSQL_ATTR_SSL_CERT (integer)

The file path to the SSL certificate.

自以下版本起 PHP 5.3.7.

PDO::MYSQL_ATTR_SSL_CIPHER (integer)

A list of one or more permissible ciphers to use for SSL encryption, in a format understood by OpenSSL. For example: DHE-RSA-AES256-SHA:AES128-SHA

自以下版本起 PHP 5.3.7.

PDO::MYSQL_ATTR_SSL_KEY (integer)

The file path to the SSL key.

自以下版本起 PHP 5.3.7.

PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT (integer)

Provides a way to disable verification of the server SSL certificate.

自以下版本起 PHP 7.0.18 and PHP 7.1.4.

PDO::MYSQL_ATTR_MULTI_STATEMENTS (integer)

Disables multi query execution in both PDO::prepare() and PDO::query() when set to FALSE.

Note, this constant can only be used in the driver_options array when constructing a new database handle.

自以下版本起 PHP 5.5.21 and PHP 5.6.5.

运行时配置

这些函数的行为受 php.ini 中的设置影响。

PDO_MYSQL Configuration Options
名字 默认 可修改范围
pdo_mysql.default_socket "/tmp/mysql.sock" PHP_INI_SYSTEM
pdo_mysql.debug NULL PHP_INI_SYSTEM
有关 PHP_INI_* 样式的更多详情与定义,见 配置可被设定范围

这是配置指令的简短说明。

pdo_mysql.default_socket string

Sets a Unix domain socket. This value can either be set at compile time if a domain socket is found at configure. This ini setting is Unix only.

pdo_mysql.debug boolean

Enables debugging for PDO_MYSQL. This setting is only available when PDO_MYSQL is compiled against mysqlnd and in PDO debug mode.

Table of Contents

User Contributed Notes

Desislav Kamenov 29-Jan-2018 08:14
There is an important undocumented attribute which disables certificate CN verification available after
5.6.22 (not sure), 7.0.18 (verified) and 7.1.15 (not sure)

PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT

possible values: true, false
default value: true

Related PHP bugs:
https://bugs.php.net/bug.php?id=71845
https://bugs.php.net/bug.php?id=71003

and github PR: https://github.com/php/php-src/pull/1913
vafa ghoreyshi atgmailcom 06-Sep-2017 04:57
If you have the error 'could not find driver' and won't able to install driver for newer linux(Fedora, Redhat, CentOS) with latest PHP7/MariaDB10/Apache2.4 get this package installed and get every things smooth.
First download latest version of epel and remi for your distribution. This links is for Fedora 26:

wget https://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
wget https://rpms.remirepo.net/fedora/remi-release-26.rpm

Than install them

rpm -Uvh remi-release-26.rpm
rpm -Uvh epel-release-6-8.noarch.rpm

Know you can use remi repository to gest php-pdo and php-mysql.

yum --enablerepo=remi install php-pdo
yum --enablerepo=remi install php-mysql

Restart the Apache

systemctl stop httpd
systemctl start httpd

Good to go!
Gerald Schneider 09-Nov-2013 08:25
This page suggests that the constant PDO::MYSQL_ATTR_FOUND_ROWS  was always available (no note "exists as of X.X"), but I found the constant missing on an installation with PHP 5.2. After switching the PHP version to 5.3.27 on the webspace the constant was available.
curt at webmasterbond dot com 15-Apr-2011 05:54
Today's PHP snapshot now has SSL support for PDO. Follow the directions here ( http://dev.mysql.com/doc/refman/5.0/en/secure-create-certs.html ) to set up MySQL and then use the following connection options:

<?php
$pdo
= new PDO(
   
'mysql:host=hostname;dbname=ssldb',
   
'username',
   
'password',
    array(
       
PDO::MYSQL_ATTR_SSL_KEY    =>'/path/to/client-key.pem',
       
PDO::MYSQL_ATTR_SSL_CERT=>'/path/to/client-cert.pem',
       
PDO::MYSQL_ATTR_SSL_CA    =>'/path/to/ca-cert.pem'
   
)
);
?>
brian at diamondsea dot com 25-Jul-2008 11:26
SQLSTATE[HY000]: General error: 2014 Cannot execute queries while other unbuffered queries are active. ...

After spending hours trying to track down why we were getting this error on a new server, after the same code ran fine on other servers, we found the problem to be an old MySQL _client_ library running on our web server, and a latest-version MySQL _server_ running on the database server's box.

Upgraded the MySQL client on the web server to the current revision and the problem went away.
miller_kurt_e at yahoo dot com 20-Jul-2008 02:03
SQLSTATE[HY000]: General error: 2014 Cannot execute queries while other unbuffered queries are active. ...

This one can be a royal pain to deal with.  Never stack statements to be executed in one go.  Nobody ever mentions this possibility in all the posts I've seen dealing with this error.

This example is a Zend Framework example but the theory is the same.

As in:

<?php
$sql
= <<<____SQL
     CREATE TABLE IF NOT EXISTS `ticket_hist` (
       `tid` int(11) NOT NULL,
       `trqform` varchar(40) NOT NULL,
       `trsform` varchar(40) NOT NULL,
       `tgen` datetime NOT NULL,
       `tterm` datetime,
       `tstatus` tinyint(1) NOT NULL
     ) ENGINE=ARCHIVE COMMENT='ticket archive';
     CREATE TABLE IF NOT EXISTS `request_hist` (
       `rqid` int(11) NOT NULL,
       `rqtid` int(11) NOT NULL,
       `rqsid` int(11) NOT NULL,
       `rqdate` datetime NOT NULL,
       `rqcode` tinyint(1) NOT NULL,
       `rssid` int(11) NOT NULL,
       `rsdate` datetime,
       `rscode` tinyint(1)
     ) ENGINE=ARCHIVE COMMENT='request archive';
     CREATE TABLE IF NOT EXISTS `relay_hist` (
       `rqid` int(5) NOT NULL,
       `sdesc` varchar(40) NOT NULL,
       `rqemail` varchar(40) NOT NULL,
       `sid` int(11) NOT NULL,
       `rlsid` int(11) NOT NULL,
       `dcode` varchar(5) NOT NULL
     ) ENGINE=ARCHIVE COMMENT='relay archive';
____SQL;
$result = $this->db->getConnection()->exec($sql);
?>

This will run fine but PDO will balk with the 'unbuffered' error if you follow this with another query.

Instead do:

<?php
$sql
= <<<____SQL
     CREATE TABLE IF NOT EXISTS `ticket_hist` (
       `tid` int(11) NOT NULL,
       `trqform` varchar(40) NOT NULL,
       `trsform` varchar(40) NOT NULL,
       `tgen` datetime NOT NULL,
       `tterm` datetime,
       `tstatus` tinyint(1) NOT NULL
     ) ENGINE=ARCHIVE COMMENT='ticket archive';
____SQL;
$result = $this->db->getConnection()->exec($sql);

$sql = <<<____SQL
     CREATE TABLE IF NOT EXISTS `request_hist` (
       `rqid` int(11) NOT NULL,
       `rqtid` int(11) NOT NULL,
       `rqsid` int(11) NOT NULL,
       `rqdate` datetime NOT NULL,
       `rqcode` tinyint(1) NOT NULL,
       `rssid` int(11) NOT NULL,
       `rsdate` datetime,
       `rscode` tinyint(1)
     ) ENGINE=ARCHIVE COMMENT='request archive';
____SQL;
$result = $this->db->getConnection()->exec($sql);

$sql = <<<____SQL
     CREATE TABLE IF NOT EXISTS `relay_hist` (
       `rqid` int(5) NOT NULL,
       `sdesc` varchar(40) NOT NULL,
       `rqemail` varchar(40) NOT NULL,
       `sid` int(11) NOT NULL,
       `rlsid` int(11) NOT NULL,
       `dcode` varchar(5) NOT NULL
     ) ENGINE=ARCHIVE COMMENT='relay archive';
____SQL;
$result = $this->db->getConnection()->exec($sql);
?>

Chopping it into individual queries fixes the problem.
rmottey at gmail dot com 09-Jan-2008 03:51
I have been getting the error below when performing multiple queries within a single page.

Setting the attribute below did not seem to work for me.

So building on previous example i am initilizing my stmt  variable on every query and a fetch all into an array. Seems to be working for me.

Error:
PDO Error 1.1: Array ( [0] => xxx[1] => yyy[2] => Lost connection to MySQL server during query )

Fix:

(PDO::setAttribute("PDO::MYSQL_ATTR_USE_BUFFERED_QUERY", true);)

<?

try {
        $dbh = new PDO('mysql:host=xxx;port=xxx;dbname=xxx', 'xxx', 'xxx', array( PDO::ATTR_PERSISTENT => false));
 $stmt = $dbh->prepare("CALL getname()");

        // call the stored procedure
        $stmt->execute();
      // fetch all rows into an array.
       $rows = $stmt->fetchAll();
       foreach ($rows as $rs)
    {
          $id = $rs['id'];
         }
//initilise the statement
unset($stmt);
$stmt = $dbh->prepare("call secondprocedure(?);");
$stmt->bindValue(1, $id);
if ( ! $stmt->execute() )
{
    echo "PDO Error 1.1:\n";
    print_r($stmt->errorInfo());
    exit;
}
unset($stmt);
} catch (PDOException $e) {
        print "Error!: " . $e->getMessage() . "<br/>";
        die();
    }
?>
davey at php dot net 06-Jun-2007 01:46
To use "PDO::MYSQL_ATTR_USE_BUFFERED_QUERY" you should call
PDO::setAttribute(PDO::MYSQL_ATTR_USE_BUFFERED_QUERY, true);

It will not work when passed into PDO::prepare()