Answer Posted / Mohd Imran
A unique key in SQL is a constraint that ensures each record in a table has a distinct value for a specified column or set of columns. A primary key is a special type of unique key that identifies each row uniquely within a table and cannot contain NULL values.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
how to start mysql server? : Sql dba
What is your daily office routine?
how to use regular expression in pattern match conditions? : Sql dba
Does group by remove duplicates?
Do we need to rebuild index after truncate?
define sql insert statement ? : Sql dba
Hi am new to PLSQL & facing problems in writing code like in SP, Functions, so any one having some SP coding with in depth explanation please share with me my Email ID suvarnaatsuvarna@rediffmail.com Or taking tanning on this please do contact me
Can delete statement be rollbacked?
If a cursor is open, how can we find in a pl/sql block?
Can we rollback truncate?
what are the advantages of sql ? : Sql dba
how many tables will create when we create table, what are they? : Sql dba
What is the best sql course?
Is primary key clustered index?
what is collation? : Sql dba