$VARCACHE

The $VARCACHE property specifies whether Oracle OLAP stores or caches variable data that is the result of the execution of a AGGREGATE function or $NATRIGGER expression.

Syntax

You add or delete a $VARCACHE property to the most recently defined or considered object (see DEFINE PROGRAM and CONSIDER) using a PROPERTY statement with the following syntax.

PROPERTY {addproperty | deleteproperty}

where

• addproperty has the following syntax.

  '$VARCACHE'  value

• deleteproperty has the following syntax.

  DELETE '$VARCACHE'

Arguments

value

One of the following TEXT expressions that indicate where Oracle OLAP should place variable data that is the result of calculations performed when the AGGREGATE function or $NATRIGGER value executes:

• VARIABLE specifies that Oracle OLAP populates the variable with data that is the result of the execution of the AGGREGATE function or $NATRIGGER property. When you specify this option, the data that is the result of the aggregation is permanently stored in the variable when the analytic workspace is updated and committed.

• SESSION specifies that Oracle OLAP caches data that is the result of the execution of the AGGREGATE function or $NATRIGGER property in the session cache (See "What is an Oracle OLAP Session Cache?"). When you specify this option, the data that is the result of the execution of the AGGREGATE function or $NATRIGGER property is ignored during updates and commits and is discarded at the end of the session.

  
  

  Important: When SESSCACHE is set to NO, Oracle OLAP does not cache the data even when you specify SESSION. In this case, specifying SESSION is the same as specifying NONE.

  
  

• NONEspecifies that Oracle OLAP calculates new variable data each time the AGGREGATE function or $NATRIGGER value executes; Oracle OLAP does not store or cache the data.

• DEFAULT specifies that you do not want Oracle OLAP to use the $VARCACHE property when determining what to do with data that is calculated by the AGGREGATE function. (See "How Oracle OLAP Determines Whether to Store or Cache Aggregated Data ".)

DELETE $VARCACHE

Deletes the $VARCACHE property.

You can also delete the $VARCACHE property along with all properties from an object by issuing a PROPERTY DELETE ALL statement.

Notes

When a $NATRIGGER expression executes, what Oracle OLAP does with variable data that results from the execution of the expression is determined based on whether or not the variable that has the $NATRIGGER property also has a $STORETRIGGERVAL property and, if not, if the value of the $NATRIGGER property is an AGGREGATE function.

When a a $NATRIGGER expression executes, Oracle OLAP goes through the following process:

1. Does the variable with the $NATRIGGER property also have a $STORETRIGGERVAL property?

   Yes. Go to step 1a.

   No. Go to step 2.

   1. Is the value of the TRIGGERSTOREOK option, 'YES' or 'NO?

      Yes. Go to step 1b.

      No. Go to step 2.

   2. Is the value of the $STORETRIGGERVAL property, YES or NO?

      Yes. Store the results of the $NATRIGGER expression. End decision-making process.

      No. Do not store the results of the $NATRIGGER expression. End decision-making process

2. Is the $NATRIGGER expression is an AGGREGATE function?

   Yes. Follow the steps described in "How Oracle OLAP Determines Whether to Store or Cache Aggregated Data " to determine what to do with the result of $NATRIGGER expression execution.

   No. Go to step 3.

3. Does the variable with the $NATRIGGER property also have a $VARCACHE property?

   Yes. Go to step 4.

   No. Go to step 5.

4. Does the $VARCACHE property have a value of DEFAULT?

   Yes. Go to step 5.

   No. Use the value of the $VARCACHE property (that is, STORE, CACHE, or NONE) to determine what happens to the variable data values that are the result of $NATRIGGER expression execution. End decision-making process.

5. Use the current setting of the VARCACHE option to determine what happens to the variable data values that are the result of $NATRIGGER expression execution. End decision-making process.

   
   

   See also: The following topics: The description of the NA keyword of the CACHE command for information on caching NA values calculated by the AGGREGATE function. "What is an Oracle OLAP Session Cache?" for a description of the data that is in a session cache.

   
   

When an AGGREGATE command executes, Oracle OLAP always stores the results of the calculation directly in the variable in the same way it stores the results of an assignment statement.

However, when an AGGREGATE function executes, Oracle OLAP sometimes stores the results of the calculation directly in the variable and sometimes caches it in the session cache. (See "What is an Oracle OLAP Session Cache?" for more information about the session cache.)

To determine where to place the data that is the result of AGGREGATE function execution, Oracle OLAP goes through the following process to determine whether to store or cache aggregated variable data:

1. Is there a CACHE statement in the specification for the aggmap that is being used by the current AGGREGATE function?

   • Yes. Go to step 2.

   • No. Go to step 3.

2. Is the CACHE statement a CACHE DEFAULT statement?

   • Yes. Go to step 3.

   • No. Use the CACHE statement in the aggregation specification to determine what to do with variable data that is the result of the calculation. End decision-making process.

3. Does the variable being aggregated have a $VARCACHE property?

   • Yes. Go to Step 4.

   • No. Go to step 5.

4. Does the $VARCACHE property have a value of DEFAULT?

   • Yes. Go to step 5.

   • No. Use the value of the $VARCACHE property determines what happens to the variable data calculated using the AGGREGATE function. End decision-making process.

5. Use the current setting of the VARCACHE option to determine what happens to the variable data calculated using the AGGREGATE function. End decision-making process.

Examples

CONSIDER v1
PROPERTY '$SVARCACHE' 'v1'