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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.
ConceptsThis section describes the different types of searches you can perform with the module and characterizes how the text search engine assigns word scores and document scores.
Perform fuzzy searchesA fuzzy search is a search for text that matches your clue closely instead of exactly. Fuzzy searches can also be referred to as pattern searches. Fuzzy searches help you return results of interest even when the search terms themselves are misspelled in the documents you are searching.
Limit the number of rows a fuzzy search returnsAt times, you might find that the search engine returns more information than you require. Use the MAX_MATCHES and WORD_SCORE tuning parameters to limit the number of rows that the search engine returns.
The MAX_MATCHES tuning parameterYou can specify the maximum number of rows the search engine returns by using the MAX_MATCHES tuning parameter.

The MAX_MATCHES tuning parameter

You can specify the maximum number of rows the search engine returns by using the MAX_MATCHES tuning parameter.

The following example shows how to specify the maximum number by using MAX_MATCHES:

SELECT id, description FROM videos
    WHERE etx_contains(description,
    Row('multimedia document editor' , 
        'PATTERN_TRANS & PATTERN_SUBS & MAX_MATCHES=3'));

It is important to note that if you specify the MAX_MATCHES tuning parameter in a query, it is possible that not all rows that satisfy all the search criteria will be returned, since this is the nature of the tuning parameter. This can cause misleading results if a subsequent qualification, different from the etx_contains() operator, is applied in the query.