PrivateCommands

Determines if commands are shared between connections.

When multiple connections execute the same command, they access common command structures controlled by a single command lock. To avoid sharing their commands and possibly placing contention on the lock, you can use PrivateCommands. This gives you better scaling at the cost of increased temporary space usage.

By default, the PrivateCommands is turned off and commands are shared.

Required Privilege

No privilege is required to change the value of this attribute.

Usage in TimesTen Scaleout and TimesTen Classic

This attribute is supported in both TimesTen Classic and TimesTen Scaleout.

Setting

Set PrivateCommands as follows:

Where to set the attribute How the attribute is represented Setting

C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef) file in TimesTen Scaleout

PrivateCommands

0 (default) - Commands are shared with other connections.

1 - Commands are not shared with any other connection.

Windows ODBC Data Source Administrator

Not applicable

Note:

  • If there are many copies of the same command, all of them are invalidated by a DDL or statistics change. Reprepare of these multiple copies takes longer when PrivateCommands = 1. With more commands DDL execution can take slightly longer.
  • When using the PrivateCommands attribute, memory consumption can increase considerably if the attribute is not used cautiously. For example, if PrivateCommands=1 for an application that has 100 connections with 100 commands, there are 10,000 commands in the system: one private command for each connection.