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Extending HCL OneDB™Beyond standard relational database objects, HCL OneDB™ can be extended to handle specialized data types, access methods, routines, and other objects. HCL OneDB™ includes many built-in extensions that are fully integrated in the database server. HCL OneDB™ also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for HCL OneDB™.
HCL OneDB™ extensions and DataBlade® modulesThese topics describe how to use built-in database extensions and separately installed DataBlade® modules.
Excalibur Text Search DataBlade® Module User's GuideThese topics describe the module and how to access and use its components.
OverviewThis section provides an overview of the module.
Components of the Excalibur Text Search DataBlade® moduleThe module has three principal components: the etx access method, the etx_contains() operator, and the supporting routines defined for the DataBlade® module.
The etx access methodUse the etx access method to call on the Excalibur Text Retrieval Library to create indexes that support sophisticated searches on table columns that contain text. The indexes that you create with the etx access method are called etx indexes.
Specify etx index parametersAn index parameter is a variable that you use to specify the characteristics of an index based on the searches you plan to perform. You set an index parameter in the USING clause of a CREATE INDEX statement when you create an etx index.

Specify etx index parameters

An index parameter is a variable that you use to specify the characteristics of an index based on the searches you plan to perform. You set an index parameter in the USING clause of a CREATE INDEX statement when you create an etx index.

For example, suppose you want to create an index identical to the index created in the previous example, but with one difference: you want to index international characters and the standard ASCII characters. To do this, you must create the index specifying the ISO character set by using the index parameter CHAR_SET.

The following example shows how to create this type of index:

CREATE INDEX desc_idx1 ON videos (description etx_clob_ops)
    USING etx (CHAR_SET = 'ISO') IN sbsp1;

By creating indexes based on likely search characteristics, you can reduce the size of your indexes and improve the relevance of search results.

You cannot alter the characteristics of an etx index after you create it. Instead, you must drop the index and then create it again with the new or altered characteristic.