Answers

Question 1

The correct answer is 4:

• The CHECK constraint is not support in a column-organized table. However, a NOT ENFORCED CHECK constraint is supported to enable query optimization.
• A table can have multiple CHECK constraints defined.
• When there are some rows that do not meet the CHECK constraint, the CHECK constraint will fail with an SQL0544N error.
• The ALTER TABLE statement can be used to define a CHECK constraint on an existing table. A sample ALTER TABLE statement is shown as follows:

ALTER TABLE demo.employee ADD CONSTRAINT check_salary CHECK (salary >=5000) ADD CONSTRAINT check_job CHECK (JOB in ('Engineer','Sales','Manager'));

Question 2

The correct answer is 2.

Unlike other constraints, information constraints are not enforced during the INSERT, UPDATE operation. However, the Db2 optimizer will evaluate the information provided...