Properties of Table Types

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Properties of Table Types

This section discusses loading tables, fast recovery, and backup and restore of table types.

Loading of Data Into a Table

Dynamic Server creates STANDARD tables that use logging by default. Data warehousing applications can have huge tables that take a long time to load. Nonlogging tables are faster to load than logging tables. You can use the CREATE RAW TABLE statement to create a RAW table or use the ALTER TABLE statement to change a STANDARD table to RAW before loading the table. After you load the table, run UPDATE STATISTICS on it.

For more information about how to improve the performance of loading very large tables, see your IBM Informix Dynamic Server Performance Guide. For more information on using ALTER TABLE to change a table from logging to nonlogging, see the IBM Informix Guide to SQL: Syntax.

Fast Recovery of Table Types

Table 32 shows fast recovery scenarios for the table types available with Dynamic Server.

Table 32. Fast Recovery of Table Types
Table Type	Fast Recovery Behavior
Standard	Fast recovery is successful. All committed log records are rolled forward, and all incomplete transactions are rolled back.
RAW	If a checkpoint completed since the raw table was modified last, all the data is recoverable. Inserts, updates, and deletions that occurred after the last checkpoint are lost. Incomplete transactions in a RAW table are not rolled back.

Backup and Restore of RAW Tables

Table 33 discusses backup scenarios for the table types available on Dynamic Server.

Table 33. Backing Up Tables on Dynamic Server
Table Type	Backup Allowed?
Standard	Yes.
Temp	No.
RAW	Yes. If you update a RAW table, you must back it up so that you can restore all the data in it. Backing up only the logical logs is not enough.

Important:

After you load a RAW table or change a RAW table to type STANDARD, you must perform a level-0 backup.

Table 34 shows restore scenarios for these table types.

Table 34. Restoring Tables on Dynamic Server
Table Type	Restore Allowed?
Standard	Yes. Warm restore, cold restore, and point-in-time restore work.
Temp	No.
RAW	When you restore a RAW table, it contains only data that was on disk at the time of the last backup. Because RAW tables are not logged, any changes that occurred since the last backup are not restored.