IBM BPM, V8.0.1, All platforms > Programming IBM BPM > Developing client applications for BPEL processes and tasks > Queries on BPEL process and task data
Query tables in Business Process Choreographer
Query tables support task and process list queries on data that is contained in the Business Process Choreographer database schema. This includes human task data and BPEL process data that is managed by Business Process Choreographer, and external business data. Query tables provide an abstraction on the data of Business Process Choreographer that can be used by client applications. In this way, client applications become independent of the actual implementation of the query table. Query table definitions are deployed on Business Process Choreographer containers, and are accessible using the query table API.
There are three types of query tables:
- Predefined query tables
- Supplemental query tables
- Composite query tables
Figure 1. Query tables in Business Process Choreographer 
Query tables are represented using similar models in the query table runtime, and you can use the query table API to query them. While predefined and supplemental query tables point directly to tables or views in the database, composite query tables compose parts of this data, which is represented in a single query table.
Query tables enhance the predefined database views and the existing query interfaces of Business Process Choreographer, and they:
- Are optimized for running process and task list queries, using performance optimized access patterns.
- Simplify and consolidate access to the information needed.
- Allow for the fine-grained configuration of authorization and filter options.
You can customize the query tables, for example, you can configure a query table so that it contains only those tasks or process instances that are relevant in a particular scenario. It is also recommended that you use query tables where performance is important, such as with high volume process list and task list queries.
The Query Table Builder is provided as an Eclipse plug-in to:
- Develop composite and supplemental query tables
- Import and export query table definitions in XML format
You can download the Query Table Builder on the SupportPacs site. Look for PA71 WebSphere Process Server - Query Table Builder. To access the link, see the related references section of this topic.
- Predefined query tables
Predefined query tables provide access to the data in the Business Process Choreographer database. They are the query table representation of the corresponding predefined Business Process Choreographer database views, such as the TASK view or the PROCESS_INSTANCE view. These predefined query tables enhance the functionality and performance of the predefined database views because they are optimized for running process and task list queries. - Supplemental query tables
Supplemental query tables in Business Process Choreographer expose to the query table API business data that is not managed by Business Process Choreographer. With supplemental query tables, this external data can be used with data from the predefined query tables when retrieving BPEL process instance information or human task information. - Composite query tables
Composite query tables in Business Process Choreographer do not have a specific representation of data in the database; they comprise of a combination of data from related predefined and supplemental query tables. Use a composite query table to retrieve the information for a process instance list or task list, such as My To Dos. - Query table development
Supplemental and composite query tables in Business Process Choreographer are developed during application development using the Query Table Builder. Predefined query tables cannot be developed or deployed. They are available when Business Process Choreographer is installed and provide a simple view on the artifacts in the Business Process Choreographer database schema. - Filters and selection criteria of query tables
Filters and selection criteria are defined during query table development using the Query Table Builder, which uses a syntax similar to SQL WHERE clauses. Use these clearly defined filters and selection criteria to specify conditions that are based on attributes of query tables. - Authorization for query tables
You can use instance-based authorization, role-based authorization, or no authorization when you run queries on query tables.
- Attribute types for query tables
Attribute types are needed in Business Process Choreographer when query tables are defined, when literal values are used in queries, and when values of a query result are accessed. Rules and mappings are available for each of the attribute types. - Query table queries
Queries are run on query tables in Business Process Choreographer using the query table API, which is available on the Business Flow Manager EJB and the REST API. - Query table queries for meta data retrieval
Queries are run on query tables in Business Process Choreographer using the query table API. Methods are available to retrieve meta data from query tables. - Internationalization for query table meta data
Internationalization is supported for query table meta data. - Query tables and query performance
Query tables introduce a clean programming model for developing client applications that retrieve lists of human tasks and BPEL processes in Business Process Choreographer. Using query tables improves the performance. Information is provided about the query table API parameters and other factors that affect the performance. - Create query tables for Business Process Choreographer Explorer
You can use query tables instead of the EJB query API to improve the performance of Business Process Choreographer Explorer. To create the query tables, use the Query Table Builder.
Queries on BPEL process and task data
Related concepts:
Business Process Archive Manager EJB API support
Related tasks:
Administer query tables
Deploying composite and supplemental query tables
Related reference:
Database views for Business Process Choreographer
Related information:
