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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.

PDO_MYSQL uses emulated prepares by default.

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 is fully supported as of PHP 7.4.4. For older releases, the mysql_xdevapi extension does support it.

警告

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.

注意:

The MySQL driver does not properly support PDO::PARAM_INPUT_OUTPUT via PDOStatement::bindParam(); while such parameters can be used, they are not updated (i.e. the actual output is ignored).

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 that 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. 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::ATTR_SSL_*, 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.

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 (int)
别名 Pdo\Mysql::ATTR_USE_BUFFERED_QUERY
PDO::MYSQL_ATTR_LOCAL_INFILE (int)
别名 Pdo\Mysql::ATTR_LOCAL_INFILE
PDO::MYSQL_ATTR_LOCAL_INFILE_DIRECTORY (int)
别名 Pdo\Mysql::ATTR_LOCAL_INFILE_DIRECTORY. Available as of PHP 8.1.0.
PDO::MYSQL_ATTR_INIT_COMMAND (int)
别名 Pdo\Mysql::ATTR_INIT_COMMAND
PDO::MYSQL_ATTR_READ_DEFAULT_FILE (int)
别名 Pdo\Mysql::ATTR_READ_DEFAULT_FILE
PDO::MYSQL_ATTR_READ_DEFAULT_GROUP (int)
别名 Pdo\Mysql::ATTR_READ_DEFAULT_GROUP
PDO::MYSQL_ATTR_MAX_BUFFER_SIZE (int)
别名 Pdo\Mysql::ATTR_MAX_BUFFER_SIZE
PDO::MYSQL_ATTR_DIRECT_QUERY (int)
别名 PDO::ATTR_EMULATE_PREPARES
PDO::MYSQL_ATTR_FOUND_ROWS (int)
别名 Pdo\Mysql::ATTR_FOUND_ROWS
PDO::MYSQL_ATTR_IGNORE_SPACE (int)
别名 Pdo\Mysql::ATTR_IGNORE_SPACE
PDO::MYSQL_ATTR_COMPRESS (int)
别名 Pdo\Mysql::ATTR_COMPRESS
PDO::MYSQL_ATTR_SERVER_PUBLIC_KEY (int)
别名 Pdo\Mysql::ATTR_SERVER_PUBLIC_KEY
PDO::MYSQL_ATTR_SSL_CA (int)
别名 Pdo\Mysql::ATTR_SSL_CA
PDO::MYSQL_ATTR_SSL_CAPATH (int)
别名 Pdo\Mysql::ATTR_SSL_CAPATH
PDO::MYSQL_ATTR_SSL_CERT (int)
别名 Pdo\Mysql::ATTR_SSL_CERT
PDO::MYSQL_ATTR_SSL_CIPHER (int)
别名 Pdo\Mysql::ATTR_SSL_CIPHER
PDO::MYSQL_ATTR_SSL_KEY (int)
别名 Pdo\Mysql::ATTR_SSL_KEY
PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT (int)
别名 Pdo\Mysql::ATTR_SSL_VERIFY_SERVER_CERT Available as of PHP 7.0.18 and PHP 7.1.4.
PDO::MYSQL_ATTR_MULTI_STATEMENTS (int)
别名 Pdo\Mysql::ATTR_MULTI_STATEMENTS

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" INI_SYSTEM
pdo_mysql.debug NULL INI_SYSTEM
有关 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 bool

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

目录

添加备注

用户贡献的备注 3 notes

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6
davey at php dot net
17 years ago
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()
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5
brian at diamondsea dot com
16 years ago
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.
up
-1
snoyes at gmail dot com
1 month ago
> change it by setting default_authentication_plugin=mysql_native_password in my.cnf

This only works in MySQL 8.0. The default_authentication_plugin variable has been removed from 8.4.
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