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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.
AdministrationThe purpose of this section is to make database administrators aware of configuration and performance issues related to the features of the module.
Choose the appropriate storage data typeYou can improve performance by choosing the appropriate storage data type for your data. This section describes the advantages and disadvantages of storing text documents in the following supported data types: BLOB, CLOB, LVARCHAR, IfxDocDesc, and IfxMRData.
The IfxMRData data type

The IfxMRData data type

The main advantage of using the multirepresentational data type IfxMRData is that it dynamically determines whether to store your document in an LVARCHAR data type or a CLOB data type, depending on the size of the document.

This feature is useful if the documents you want to store in a single column of a table vary greatly in size, where some fit in an LVARCHAR data type and some do not. It is preferable to store documents in LVARCHAR columns if at all possible, since it is faster to insert documents into and retrieve documents from this data type than into smart large object types such as CLOB. IfxMRData lets the data type itself decide where to store the data so that you do not have to decide at the time you create the table.

IfxMRData is also designed to improve I/O performance of documents that contain only standard ASCII text. Therefore, if your documents do not contain binary data, storing them in a column of this data type might improve performance.