Answer / vineet

A Table can have only one primary key but it is possible to
have more than 1 primary key attributes i.e candidate key.

Answer / avdhesh

One Table can contain only One Pk But can Have more than One
Unique Key

Answer / balaji

a table can have only one primary key.
u can make another primary key
that is called a composite primary key

Answer / saurabh

No, a table can have one and only one primary key.

Answer / sandeep gogoi

yes! it possibly have 2 primary keys as a combination of
such keys should not repeated!...

Answer / uhaish

Yes and it can and the number of primary keys in a single
table is not limited and can be 3,4, unlimited .The concept
is imagine 2 primary keys cols in a table as one primary
key col .
which means if you have two cols A and B both are primary
key by defination then..
AB
00
01
02
12
21
21
22

,see individually a primary key col is not anymore unique
but as hole its unique no other row in a table can have the
same combination of these two primary keys i.e '02' cannot
be repeated .

Answer / murali krishna penke

we can create more than one primary key in a table. the
maximum allowed to create primary keys for columns is 16,
but we call it primary key for one column only and the
remaining we call it as composite primary key..

create table TestPrimaryKey(ID int,Name nvarchar(50),Email
nvarchar(50),Phone nvarchar(12),cellphone nvarchar
(10),primary key(ID,Name,Email,Phone,cellphone))

the above table creates primary key for all above mentioned
columns.

Answer / antonis flangofas

ofc you can, stop giving to ppl wrong answers here it is

CREATE TABLE track(
album CHAR(10),
disk INTEGER,
posn INTEGER,
song VARCHAR(255),
PRIMARY KEY (album, disk, posn)
)

if you want to avoid to have id you use this way.

Answer / dan

Kumar Navdeep Shanker

I have created the table provided and it works well.
You said that is possible to have two primary key, I am
sorry I have to disagree with you and all who said yes.

Let me explain using your table

cno balance cname
1 2 w
2 2 x
1 3 r
primary key no two tuple have the same value

what you are providing is a composite key

Thus, we can have more than one key in a table that the
compinaition of the keys are unique

BUT we have only one primary key that means it is unique

Please correct me if i am wrong

Answer / san

Yes we can keep but it become composite key
means primary key for that perticular coloum only

Can we have two clustered index on a table?

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