Description
The modify statement enables you to perform the following operations:
• Change the storage structure of the specified table or index.
• Specify the number of pages allocated for a table or index, and the number of pages by which it grows when it requires more space.
• Add pages to a table.
• Reorganize a btree index.
• Move a table or index, or portion thereof, from one location to another.
• Spread a table over many locations or consolidate a table onto fewer locations.
• Delete all rows from a table and release its file space back to the operating system.
• Specify whether an index is recreated when its base table is modified.
• Specify how unique columns are checked during updates: after each row is inserted or after the update statement is completed.
You can change a table's location and storage structure in the same modify statement.
The modify statement operates on existing tables and indexes. When you modify a table, the DBMS Server destroys any indexes that exist for the specified table (unless the index was created with persistence, or the table is a btree and you are modifying the table to reorganize its index).
(The modify statement does not fire rules defined for the specified tables. For details about rules, see the SQL Reference Guide.)