Pdo Methods

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beginTransaction

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Initiates a transaction

Turns off autocommit mode. While autocommit mode is turned off, changes made to the database via the PDO object instance are not committed until you end the transaction by calling PDO::commit(). Calling PDO::rollBack() will roll back all changes to the database and return the connection to autocommit mode.

Some databases, including MySQL, automatically issue an implicit COMMIT when a database definition language (DDL) statement such as DROP TABLE or CREATE TABLE is issued within a transaction. The implicit COMMIT will prevent you from rolling back any other changes within the transaction boundary.

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commit

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Commits a transaction, returning the database connection to autocommit mode until the next call to PDO::beginTransaction() starts a new transaction.

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__construct

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Creates a PDO instance to represent a connection to the requested database.

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errorCode

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Returns a SQLSTATE, a five characters alphanumeric identifier defined in the ANSI SQL-92 standard. Briefly, an SQLSTATE consists of a two characters class value followed by a three characters subclass value. A class value of 01 indicates a warning and is accompanied by a return code of SQL_SUCCESS_WITH_INFO. Class values other than '01', except for the class 'IM', indicate an error. The class 'IM' is specific to warnings and errors that derive from the implementation of PDO (or perhaps ODBC, if you're using the ODBC driver) itself. The subclass value '000' in any class indicates that there is no subclass for that SQLSTATE.

PDO::errorCode() only retrieves error codes for operations performed directly on the database handle. If you create a PDOStatement object through PDO::prepare() or PDO::query() and invoke an error on the statement handle, PDO::errorCode() will not reflect that error. You must call PDOStatement::errorCode() to return the error code for an operation performed on a particular statement handle.

Returns NULL if no operation has been run on the database handle.

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errorInfo

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Fetch extended error information associated with the last operation on the database handle

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exec

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PDO::exec() executes an SQL statement in a single function call, returning the number of rows affected by the statement.

PDO::exec() does not return results from a SELECT statement. For a SELECT statement that you only need to issue once during your program, consider issuing PDO::query(). For a statement that you need to issue multiple times, prepare a PDOStatement object with PDO::prepare() and issue the statement with PDOStatement::execute().

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getAttribute

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This function returns the value of a database connection attribute. To retrieve PDOStatement attributes, refer to PDOStatement::getAttribute().

Note that some database/driver combinations may not support all of the database connection attributes.

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getAvailableDrivers

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This function returns all currently available PDO drivers which can be used in DSN parameter of PDO::__construct(). This is a static method.

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lastInsertId

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Returns the ID of the last inserted row, or the last value from a sequence object, depending on the underlying driver. For example, PDO_PGSQL() requires you to specify the name of a sequence object for the name parameter.

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prepare

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Prepares an SQL statement to be executed by the PDOStatement::execute() method. The SQL statement can contain zero or more named (:name) or question mark (?) parameter markers for which real values will be substituted when the statement is executed. You cannot use both named and question mark parameter markers within the same SQL statement; pick one or the other parameter style.

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query

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Executes an SQL statement, returning a result set as a PDOStatement object

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quote

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PDO::quote() places quotes around the input string (if required) and escapes special characters within the input string, using a quoting style appropriate to the underlying driver.

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rollBack

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Rolls back the current transaction, as initiated by PDO::beginTransaction(). It is an error to call this method if no transaction is active.

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setAttribute

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Sets an attribute on the database handle. Some of the available generic attributes are listed below; some drivers may make use of additional driver specific attributes.