___________ defines rules regarding the values allowed in columns and is the standard mechanism for enforcing database integrity.
A. Column
B. Constraint
C. Index
D. Trigger
Answer:A
___________ defines rules regarding the values allowed in columns and is the standard mechanism for enforcing database integrity.
A. Column B. Constraint C. Index D. Trigger
Explanation: SQL constraints are used to specify rules for the data in a table.If there is any violation between the constraint and the data action, the action is aborted by the constraint.