Answer Posted / rajshri.20
SQL constraints are used to specify rules for the data in a table.
NOT NULL - Indicates that a column cannot store NULL value
UNIQUE - Ensures that each row for a column must have a unique value
PRIMARY KEY - A combination of a NOT NULL and UNIQUE. Ensures that a column (or combination of two or more columns) have an unique identity which helps to find a particular record in a table more easily and quickly
FOREIGN KEY - Ensure the referential integrity of the data in one table to match values in another table
CHECK - Ensures that the value in a column meets a specific condition
DEFAULT - Specifies a default value when specified none for this column
| Is This Answer Correct ? | 2 Yes | 0 No |
Post New Answer View All Answers
How to open and close an explicit cursor in oracle?
Explain the use of grant option in exp command.
how can we store any pdf file in oracle
How to delete all rows a table in oracle?
How do you find current date and time in oracle?
How to use "in out" parameter properly?
What is ADDM Advisor in Oracle?
Explain about your project and its relation to the current job position you are applying to?
Can group functions be mixed with non-group selection fields?
What do database buffers contain?
how may join possible between (requisition with purchase order)
How to drop an index in oracle?
Write a trigger example in oracle?
How to commit the current transaction in oracle?
can u send the sql dumps to sivakumarr1987@gmail.com plz help me