Interested to Buy Any Domain ? << Click Here >> for more details...
What is the diff. bwt. primary key and unique key?
- 4 Answers
- 6493 Views
- I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / janhvee
diff. between primary key and unique is unique key can be
null but primary key can't be null.
one table can have only one primary key but unique key can
be multiple keys
| Is This Answer Correct ? | 17 Yes | 0 No |
Answer / rakesh ranjan
IN PRIMARY KEY IS ONLY IN ANY TABLE BUT WHEN WE TALKING
ABOUT UNIQUE KEY, IT CAN BE NULL.
| Is This Answer Correct ? | 5 Yes | 1 No |
primary is not allow null value.but unique can be allow null
value
| Is This Answer Correct ? | 3 Yes | 0 No |
Answer / sonu kumar
primary of any table can't be null but unique can be
primary key may be a unique key but unique can't be a primary key b/c primary key of any relation cant be a null value
| Is This Answer Correct ? | 0 Yes | 0 No |
Explain the storage engines in mysql?
What is the use of mysql_fetch_array () function in php?
How do I show users in mysql?
How do I show columns in mysql?
What port is mysql running on?
What is information_schema in mysql?
Why use stored procedures in mysql?
How you will show all data from a table.
how you will show all records not containing the name "sonia" and the phone number '9876543210' order by the phone_number field.
what is mysql optimization in brief?
What is clob datatype?
Which is best pdo or mysqli?
-
Oracle (3253) - SQL Server (4518)
- MS Access (429)
- MySQL (1402)
- Postgre (483)
- Sybase (267)
- DB Architecture (141)
- DB Administration (291)
- DB Development (113)
- SQL PLSQL (3330)
- MongoDB (502)
- IBM Informix (50)
- Neo4j (82)
- InfluxDB (0)
- Apache CouchDB (44)
- Firebird (5)
- Database Management (1411)
- Databases AllOther (288)
