Machine-translated by Google. Questions are authored in English.
Top

Discussion

The SQL CHECK constraint is fully defined by the SQL-92 standard, and is consistently implemented by all DBMS vendors.

  • A.True
  • B.False

Answer: B

Correct answer: False

CHECK is defined by the standard but implemented with real differences between products - in what expressions are permitted, whether subqueries may appear, and when the condition is evaluated. Portable code must therefore keep CHECK constraints simple, and complex rules are often placed in triggers instead.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.