Exam C2090-600 topic 1 question 45 discussion

The correct answers are then : B. ALTER TABLE tab1 DROP COLUMN col1 C. ALTER TABLE tab1 ALTER COLUMN col1 SET NOT NULL

Certain ALTER TABLE operations, like dropping a column, altering a column type, or altering the nullability property of a column may put the table into a reorg pending state. In this state, many types of queries cannot be run; you must perform a table reorganization before the table becomes available for some types of queries. However, even with the table in a reorg pending state, in most cases, you can still run the ALTER TABLE statement multiple times without having to run the REORG TABLE command. REFERENCE : https://www.ibm.com/support/knowledgecenter/en/SSEPGG_11.1.0/com.ibm.db2.luw.admin.dbobj.doc/doc/r0053739.html See section "Multiple ALTER TABLE operations within a single unit of work"