Connection-Level Variables

Connection-level variables are declared by the user, and can be used in procedures or in batches of SQL statements to hold information.

Connection-level variables are declared with the CREATE VARIABLE statement. The CREATE VARIABLE statement can be used anywhere except inside compound statements. Connection-level variables can be passed as parameters to procedures.

The syntax for CREATE VARIABLE is:

CREATE VARIABLE variable-name data-type

When a variable is created, it is initially set to NULL. You can set the value of connection-level variables in the same way as local variables, using the SET statement or using a SELECT statement with an INTO clause.

Connection-level variables exist until the connection is terminated, or until you explicitly drop the variable using the DROP VARIABLE statement. The following statement drops the variable con_var:

DROP VARIABLE con_var

Example

The following batch of SQL statements illustrates the use of connection-level variables.
```
CREATE VARIABLE con_var INT;
SET con_var = 10;
MESSAGE 'con_var = ', con_var;
```
Running this batch from ISQL displays this message on the server window:
```
con_var = 10
```

Compatibility

Adaptive Server Enterprise does not support connection-level variables.