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PDO->__construct()
(no version information, might be only in CVS)
PDO->__construct() -- Creates a PDO instance representing a connection to a databasePopis
class PDO {PDO __construct ( string dsn [, string username [, string password [, array driver_options]]] )
}
Creates a PDO instance to represent a connection to the requested database.
Seznam parametrů
- dsn
The Data Source Name, or DSN, contains the information required to connect to the database.
In general, a DSN consists of the PDO driver name, followed by a colon, followed by the PDO driver-specific connection syntax. Further information is available from the PDO driver-specific documentation.
The
dsn
parameter supports three different methods of specifying the arguments required to create a database connection:- Driver invocation
dsn
contains the full DSN.- URI invocation
dsn
consists of uri: followed by a URI that defines the location of a file containing the DSN string. The URI can specify a local file or a remote URL.uri:file:///path/to/dsnfile
- Aliasing
dsn
consists of a namename
that maps to pdo.dsn.name
in php.ini defining the DSN string.Poznámka: The alias must be defined in php.ini, and not .htaccess or httpd.conf
- username
The user name for the DSN string. This parameter is optional for some PDO drivers.
- password
The password for the DSN string. This parameter is optional for some PDO drivers.
- driver_options
A key=>value array of driver-specific connection options.
Errors/Exceptions
PDO->__construct() throws a PDOException if the attempt to connect to the requested database fails.
PÅ™Ãklady
PÅ™Ãklad 2. Create a PDO instance via URI invocation The following example assumes that the file /usr/local/dbconnect exists with file permissions that enable PHP to read the file. The file contains the PDO DSN to connect to a DB2 database through the PDO_ODBC driver:
The PHP script can then create a database connection by simply passing the uri: parameter and pointing to the file URI:
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PÅ™Ãklad 3. Create a PDO instance using an alias The following example assumes that php.ini contains the following entry to enable a connection to a MySQL database using only the alias mydb:
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PDO->commit() | Nahoru |