How Catalog Manager handles lock contention

Db2 performs normal locking as part of reading the rows. For example, if the table space contains only one table and the SELECT statement has no WHERE clause, Db2 might escalate row or page locks to a table space lock, since all rows in the table are being read.

If you are browsing data, the SELECT statement is modified to append a FOR FETCH ONLY clause to prevent Db2 from holding locks for fetched rows. Data browsing performs as if the Hold rows during edit option was set to N. Because data cannot be edited in data browsing mode, comparing and overwriting data are meaningless.

How these locks affect your other applications depends on what isolation level you set when you bound packages for Catalog Manager and other applications, and what lock options were specified when the table space containing the table was created.

For more information about how locking affects your applications, see the Installation System documentation, Customizing BMC products and solutions for Db2, and the IBM documentation.