DSN
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DSN

DSN – The Data Source Name

Description

To connect to a database through PEAR::MDB2, you have to create a valid DSN - data source name. This DSN consists in the following parts:

phptype: Database backend used in PHP (i.e. mysql , pgsql etc.)
dbsyntax: Database used with regards to SQL syntax etc.
protocol: Communication protocol to use ( i.e. tcp, unix etc.)
hostspec: Host specification (hostname[:port])
database: Database to use on the DBMS server
username: User name for login
password: Password for login
proto_opts: Maybe used with protocol
option: Additional connection options in URI query string format. options get separated by &. The Following table shows a non complete list of options:

List of options
Name	Description	Type
`charset`	Some backends support setting the client charset. (Invokes setCharset(string $charset, [resource $connection = null])	string
`new_link` [boolean]	Some RDBMS do not create new connections when connecting to the same host multiple times. If this option is set to TRUE it will attempt to force a new connection.	boolean

The DSN can either be provided as an associative array or as a string. The array format is preferred, since it doesn't require a further parsing step (see the Connecting chapter for an example). The string format of the supplied DSN is in its fullest form:

phptype(dbsyntax)://username:password@protocol+hostspec/database?option=value

Most variations are allowed:

phptype://username:password@protocol+hostspec:110//usr/db_file.db
phptype://username:password@hostspec/database
phptype://username:password@hostspec
phptype://username@hostspec
phptype://hostspec/database
phptype://hostspec
phptype:///database
phptype:///database?option=value&anotheroption=anothervalue
phptype(dbsyntax)
phptype

The currently supported database backends are:

fbsql  -> FrontBase
ibase  -> InterBase / Firebird (requires PHP 5)
mssql  -> Microsoft SQL Server (NOT for Sybase. Compile PHP --with-mssql)
mysql  -> MySQL
mysqli -> MySQL (supports new authentication protocol) (requires PHP 5)
oci8   -> Oracle 7/8/9/10
pgsql  -> PostgreSQL
querysim -> QuerySim
sqlite -> SQLite 2

A second DSN format is supported

phptype(syntax)://user:pass@protocol(proto_opts)/database

If your database, option values, username or password contain characters used to delineate DSN parts, you can escape them via URI hex encodings:

: = %3a   / = %2f   @ = %40
+ = %2b   ( = %28   ) = %29
? = %3f   = = %3d   & = %26

Please note, that some features may be not supported by all database backends.

Example

Connect to database through a socket

mysql://user@unix(/path/to/socket)/pear

Connect to database on a non standard port

pgsql://user:pass@tcp(localhost:5555)/pear

Connect to SQLite on a Unix machine using options

sqlite:////full/unix/path/to/file.db?mode=0666

Connect to SQLite on a Windows machine using options

sqlite:///c:/full/windows/path/to/file.db?mode=0666

Connect to MySQLi using SSL

mysqli://user:pass@localhost/pear?key=client-key.pem&cert=client-cert.pem

Connect to Oracle using Service name

oci8://username:password@foo.example.com[:port]/?service=service

Connect to Oracle using "Easy Connect" syntax

username/password@[//]host[:port][/service_name]

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