Part 4: Check Constraints in SQL
A check constraint on a column or set of columns requires that a specified condition…
Read moreasrblogger
Data Dictionary in Oracle
The central set of read-only reference tables and views of each Oracle database is known…
Read morePart 2: NOT NULL & Unique Constraints in SQL
NOT NULL Constraints The NOT NULL constraint ensures that the column contains no null values.…
Read morePart 1: Constraints in SQL
Purpose: Use a constraint to define an integrity constraint—a rule that restricts the values in…
Read more