What is a constraint. Types of constraints ?

Answer Posted / pavani

Constraint means it is rule which you want to apply on the
table. There are two types of constraints.
1. Column Constraints: Applicable for that column only.
2. Table Constraints: Applicable for more than one column.

Column Constraints:
a. unique b. not null c. primary key d. foreign key
e.default f. check

Table constraints:
a. unique b. primary key c. foreign key d. check

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