You can use nonlogging raw tables in a logging database to speed up the initial loading and validation of data in Dynamic Server 9.40, 9.30, or 9.2x, which creates standard tables that use logging by default. Data warehousing and other applications can have very large tables that take a long time to load. Nonlogging tables are faster to load than logging tables.
To create a nonlogging table for loading, you can use the CREATE RAW TABLE statement, or you can use the ALTER TABLE statement to change the table type from STANDARD to RAW. Tables of type RAW do not allow indexes or referential constraints, so the initial loading is faster than with tables of type STANDARD. After the loading of a raw table is complete, you can change it to a logging table (in a logging database) by changing the table type to STANDARD. Then you can use ALTER TABLE statements to add referential constraints to the table and CREATE INDEX statements to add indexes. For more information on these SQL statements, see the IBM Informix: Guide to SQL Syntax.
To load raw tables, you can use any data loading utility, such as dbimport or HPL in express mode. After you load data, perform a level-0 backup. Before you modify any data in a raw table or use it in a transaction, change the table type to STANDARD.
If an error or failure occurs during the loading of a raw table, the resulting data is whatever was on the disk at the time of the failure.
The dbexport and dbschema utilities support the CREATE RAW TABLE and ALTER TABLE...TYPE (RAW) statements.
For more information on nonlogging tables, see your IBM Informix: Administrator's Guide. For more information on how to improve the performance of loading very large tables, see your IBM Informix: Performance Guide. For more information on the ALTER TABLE statement, see the IBM Informix: Guide to SQL Syntax.
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