DB2 Version 9.7 for Linux, UNIX, and Windows

SYSTS_UPDATE procedure - Update the text search index

This procedure updates the text search index to reflect the current contents of the text column with which the index is associated.

While the update is being performed, a search is possible. Until completion of the update, the search operates on a partially updated index.

The procedure issues an UPDATE INDEX text search administration command on the database server.

Syntax


>>-SYSTS_UPDATE--(--index_schema--,--index_name--,-------------->

>--update_options--,--message_locale--,--message--)------------><

The schema is SYSPROC.

Procedure parameters

index_schema

An input argument of type VARCHAR(128) that specifies the schema of the text search index. The index_schema must follow the naming restriction for DB2® schema names. If the argument is null or an empty string, the value of CURRENT SCHEMA is used. The index_schema is case-sensitive.

index_name

An input argument of type VARCHAR(128) that specifies the name of the index. Together with index_schema, it uniquely identifies a text search index in a database. The index_name is case-sensitive.

update_options

An input argument of type VARCHAR(32K) that specifies update options. The possible values are:

USING UPDATE MINIMUM: this setting respects the UPDATE MINIMUM settings from the CREATE INDEX text search administration command and the SYSTS_CREATE procedure.
UPDATEAUTOCOMMIT: this setting overrides the commitcount defined for the text index for the duration of this update execution.
NULL or an empty string ("): the update is unconditionally started when the procedure is called.

message_locale

An input argument of type VARCHAR(33) that specifies the locale to be used for any error message returned. If the argument is null or an empty string, or the message files for the specified locale are not available on the server, 'en_US' is used.

message

An output argument of type VARCHAR(32K) that specifies a warning or informational message for a successfully completed operation.

Authorization

The privileges held by the authorization ID of the statement must include at least one of the following authorities:

CONTROL privilege on the table on which the text index is defined
DATAACCESS authority

Examples

Example 1: In the following example, the text search index that was created with index_schema 'db2ts' and index_name 'myTextIndex' is being updated. A NULL value in the place of the update_options means that an update is unconditionally started when the stored procedure is called. Any error messages are requested to be returned in English. When the procedure succeeds, the output parameter message indicative of the successful operation is returned to the caller.

  CALL SYSPROC.SYSTS_UPDATE('db2ts', 'myTextIndex', '', 'en_US', ?)

The following example is a sample output from this query.

  Value of output parameters
  --------------------------
  Parameter Name  : MESSAGE
  Parameter Value : Operation completed successfully.

  Return Status = 0

Example 2: In the following example, SYSTS_UPDATE is called to update a text search index with index_schema 'db2ts' and index_name 'myTextIndex'. This index does not exist and results in an error.

  CALL SYSPROC.SYSTS_UPDATE('db2ts', 'myTextIndex', 'USING UPDATE MINIMUM', 
		'en_US', ?)

The following example is a sample output from this query.

  SQL20427N An error occurred during a text search administration 
  procedure or command. The error message is "CIE00316 Text search 
  index "db2ts"."myTextIndex" does not exist. ". SQLSTATE 38H14

Usage notes

Text search administration procedures use an existing connection to the database. The current transaction might be committed or rolled back depending on the completion of the procedures. As such, you might want to commit all transaction changes to avoid any unexpected impact from such a commit or rollback. One way to achieve this is to turn on AUTOCOMMIT.
Multiple procedures or commands cannot be run concurrently on a text search index if they might conflict. Some of the conflicting procedures and commands are:
- SYSTS_ALTER procedure or ALTER INDEX db2ts command
- SYSTS_CLEAR_EVENTS procedure or CLEAR EVENTS FOR INDEX db2ts command
- SYSTS_DISABLE procedure or DISABLE DATABASE FOR TEXT db2ts command
- SYSTS_DROP procedure or DROP INDEX db2ts command
- STOP FOR TEXT db2ts command
- SYSTS_UPDATE procedure or UPDATE INDEX db2ts command
If there is a conflict, the procedure returns an SQLCODE -20426 and SQLSTATE 38H13.
This procedure does not return until all index update processing is completed. The duration depends on the number of documents to be indexed and the number of documents already indexed. The collection name for the index can be retrieved from the SYSIBMTS.TSCOLLECTIONNAMES view (column COLLECTIONNAME).
When there are individual document errors, the documents must be corrected. The primary keys of the erroneous documents can be looked up in the event table for the index. By changing the corresponding rows in the user table, the next call to SYSTS_UPDATE will reprocess these documents.
When this procedure is run,
- rows are inserted into the event table (including parser error information). Information is deleted from the index staging table in case of incremental updates. Before the first update, it creates triggers on the user table.
- the collection is updated: new or changed documents are parsed and indexed and deleted documents are discarded from the index.