What is the diff. bwt. primary key and unique key?
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 |
If you are assigned a task, to find the information of procedures. What are the basic commands that you will use to do so?
What is username in mysql?
How do I run a query in mysql?
i made a table in sql server 2000 and in a column i want to add image path of a picture present in my hardisk... so using insert statement how will i insert the path of the image in the table??
Is mysql relational database?
How do I connect to a database in mysql workbench?
Is there an object-oriented version of MySQL library functions?
Are stored procedures precompiled?
how to take mysql database structure backup
How to use rank function in mysql?
Why is mysql popular?
What is difference between mysql and mysql server?