StmtCache database parameter
Description
Specifies whether SQL
statement caching is enabled on the client.
Controls
-
I10 Informix
Syntax
|
1 |
StmtCache='<span>value</span>' |
|
Parameter |
Description |
|---|---|
|
value |
Specifies whether SQL statement
|
Default
StmtCache=0
Usage
In IDS 9.2.1 and later, the database server uses the SQL statement cache (SSC) to store SQL statements across user sessions.
When any user executes a statement already stored in the SQL statement cache, the database
server does not parse and optimize the statement again, resulting
in improved performance. The statement must be a SELECT, UPDATE, DELETE,
or INSERT statement, and it cannot contain user-defined
routines.
There are several ways to configure caching on the server.
The SET STATEMENT CACHE statement
takes precedence over the STMT_CACHE environment variable
and the STMT_CACHE configuration parameter. You must enable
the SQL statement cache, either
by setting the STMT_CACHE configuration parameter or by
using the Informix onmode utility, before the SET
STATEMENT CACHE statement can execute successfully.
You can set the StmtCache DbParameter on the System tab page
in the Database Profile Setup dialog box for I10 connections to
turn SQL statement caching on or
off on the client. However, the server must be configured to support SQL statement caching before you
can access the cache from the client.
For more information about Informix SQL statement
caching, see the IBM Informix Dynamic Server Performance Guide
.
Examples
To specify that the client can access data from the SQL statement cache if it is configured
on the server:
-
Database profile
Select the Enable SQL Statement
Cache check box on the System page in the Database Profile Setup
dialog box. -
Application
Type the following in code:
1SQLCA.DbParameter="StmtCache=1"