Copyright © TIBCO Software Inc. All Rights Reserved
Copyright © TIBCO Software Inc. All Rights Reserved


Chapter 18 Functions : Oracle Coherence Cache Query Functions

Oracle Coherence Cache Query Functions
TIBCO BusinessEvents Express  This section relates to Cache OM functionality and is not relevant if you are using TIBCO BusinessEvents Express edition.
These functions work only with a Coherence cluster. For information on using Oracle Coherence with TIBCO BusinessEvents, see Chapter 24, Cache OM and Cluster Configuration.
You can also query a Coherence cache using the method explained in the section To Query the Cache Using BQL Queries.
Also see Indexing for More Efficient Cache Queries.
Constants, Extractors, and Filters Categories
The Coherence category has Constants and Extractors functions which are used in conjunction with functions in the Filters category.
Extractor functions return values for properties of different types.
Constants functions wrap constants so they can be used in filter functions. For example if a filter checks for X = 10, you would first wrap 10 using C_IntConstant().
Functions in the Filters category enable you to use various criteria to identify a set of objects in the cache for a query. You can pass the filter to a query function.
The C_RuleFunction() function allows you to specify a rule function containing a custom filter condition.
Query Category
Query category functions operate only on the cache  Unlike the C_CacheLoad*() functions, the query functions do not look in the backing store if objects are not found in the cache.
If a backing store is used  Do not use query functions that delete or modify values if a backing store is used. Instead use a query to return the IDs of the entities you want to delete and use Instance.deleteInstance() or Event.consumeEvent() as needed.
C_CacheInvoke()
C_CacheOnlyMode_DeleteConcepts
C_CacheOnlyMode_DeleteEntities
C_CacheOnlyMode_QueryConcepts
C_CurrentContext
C_EntryHasNext
C_EntryIterator
C_EntryNextValue
C_KeyHasNext
C_KeyIterator
C_KeyNextValue
C_QueryAction
C_QueryAndLoadConcepts
C_QueryConcepts
C_QueryEvents
C_QueryEvents_Order
C_QueryIDs
Query functions take various actions for a specified entity or set of entities. For example, C_CacheInvoke() allows you to invoke a rule function for all matching entities in the cache.
For some functions you can specify the entities by passing a filter (from the Filters category).
Tool tips in the user interface (and reproduced in the TIBCO BusinessEvents Functions Reference) explain how to use the functions singly or in combination to achieve the desired results.
The C_CacheOnlyMode*() functions are for use with entities that use cache-only cache mode.
 

Copyright © TIBCO Software Inc. All Rights Reserved
Copyright © TIBCO Software Inc. All Rights Reserved