Logical Servers and Policies (IQ)

Sybase IQ v16 and higher supports logical servers, which provide the only means to access the multiplex  server  nodes. PowerDesigner models logical servers and logical server policies as extended objects with a stereotype of <<LogicalServer>> and <<LogicalServerPolicy>> respectively.

Creating a Logical Server

You can create a logical server in any of the following ways:

  • Select Model > Logical Servers to access the List of Logical Servers, and click the Add a Row tool.

  • Right-click the model (or a package) in the Browser, and select New > Logical Server.

Creating a Logical Server Policy

You can create a logical server policy in any of the following ways:

  • Select Model > Logical Server Policies to access the List of Logical Policies, and click the Add a Row tool.

  • Right-click the model (or a package) in the Browser, and select New > Logical Server Policy.

Logical Server and Logical Server Policy Properties

You can modify an object's properties from its property sheet. To open a logical server or logical server policy property sheet, double-click its Browser entry in the Logical Servers or Logical Server Policies folder.

The following extended attributes are available on the General tab:

Name

Description

With stop server

Automatically shuts down all servers in the logical server when the TEMP_DATA_IN_SHARED_TEMP option is changed directly or indirectly.

Scripting name: WithStopServer

The following extended attributes are available on the Sybase IQ tab of logical servers:

Name

Description

Membership

Lists the multiplex nodes (see Multiplex Servers (IQ)) of the logical server.

Select the Add for logical coordinator membership option to specifies a logical server membership to the current coordinator.

Scripting name: Membership, MembershipForLogicalCoordinator

Policy

Specifies the logical server policy applied to the server.

Scripting name: Policy

The following extended attributes are available on the Options tab of logical server policies:

Name

Description

DQP enabled

Specifies how query processing is distributed:
  • 0 - Not distributed
  • 1 - [default] Distributed as long as a writable shared temporary file exists.
  • 2 - Distributed over the network, and the shared temporary store is not used

Scripting name: DqpEnabled-disp

Allow coordinator as member

[ROOT policy only] Specifies that the coordinator can be a member of any user-defined logical server. Enabled by default.

Scripting name: AllowCoordinatorAsMember-disp

Login redirection

Enables login redirection for logical servers governed by specified login policy. By default, login redirection is disabled at the logical server level, allowing external connection management.

Scripting name: LoginRedirection-disp

Redirection waiters threshold

Specifies how many connections can queue before IQ redirects a connection to this logical server to another server.

Scripting name: RedirectionWaitersThreshold-disp

Temp data in shared temp

Enables temporary table data and eligible scratch data writes to the shared temporary store, provided that the shared temporary store has at least one read-write file added.

Scripting name: TempDataInSharedTemp-disp