CONNECT

Description

Establishes a connection to a database. Optionally, the CONNECT statement can also specify a name for the connection and a user-name/password for authentication.

Syntax

CONNECT TO connect_string

     [AS connection_name]

     [USER user_name]

     [USING password]

connect_string::

     { DEFAULT

     | db_name

     | port@host_name:db_name }

Arguments

Arguments to CONNECT must either be string literals enclosed in quotation marks or character-string host variables.

connect_string

The string that specifies the database to connect to. If the CONNECT statement specifies DEFAULT, c-treeACE SQL tries to connect to the environment-defined database, if any. (How you define the default database varies between operating systems. On Unix, the value of the DB_NAME environment variable specifies the default connect string.)

The connect string can be a simple database name or a complete connect string. A complete connect string has the following components:

connection_name

The name for the connection for use in DISCONNECT and SET CONNECTION statements. If the CONNECT statement omits a connection name, the default is the name of the database. Connection names must be unique.

user_name

User name for authentication of the connection. c-treeACE SQL verifies the user name against a corresponding password before it connects to the database. If omitted, the default value depends on the environment. (On UNIX, the value of the DH_USER environment variable specifies the default user name. If DH_USER is not set, the value of the USER environment variable specifies the default user name.)

password

Password for authentication of the connection. c-treeACE SQL verifies the password against a corresponding user name before it connects to the database. If omitted, the default value depends on the environment.

(On Unix, the value of the DH_PASSWD environment variable specifies the default password.)

Notes

• Arguments to CONNECT must either be string literals enclosed in quotation marks or character-string host variables.
• An application can connect to more than one database at a time, with a maximum of 10 connections. However, the application can actually gain access to only one database at a time. The database name specified in the CONNECT statement becomes the active one.
• If an application executes an c-treeACE SQL statement before connecting to a database, c-treeACE SQLtries to connect to the database specified through the DB_NAME environment variable, if that environment variable is defined. If the connection is successful, the c-treeACE SQL statement executes on that database.

Authorization

None.

Examples

The following examples illustrate the CONNECT statement:

• The first statement shown connects to the “salesdb” database on the local system.
• The second statement connects to the “custdb” database on the local system using a network protocol.
• The third statement connects to the “custdb” database on the local mode, using the local pipe IPC protocol.
• The fourth statement connects to the environment-defined database by default (if any).

CONNECT TO "salesdb" AS "sales_conn";

CONNECT TO "6597@localhost:custdb" AS "cust_conn";

CONNECT TO "6597@testbox:custdb" AS "cust_conn";

CONNECT TO DEFAULT;