Can we have more than one primary key in table

Question

can we have more than one primary key in table

Faisal Pathan · Answer

No, we can not create. normally when we are new to RDBMS are often to get confused with the restriction of single Primary Key in table here we can use concept of Composite Key. If the Primary Key is defined using more that one columns,Its call Composite Key or Composite Primary Key.

Kalyani Shevale · Answer

A table can have only one primary key, which may consist of single or multiplefields. When multiple fields are used as a primary key, they are called a compositekey. If a table has a primary key defined on any field(s), then you cannot have two records having the same value of that field(s).

Amit Gupta · Answer

Yes definitely, select the columns in the designer that you want to make primary key -> right click -> primary key. That's it

Code Alone · Answer

In RDBMS you can't create multiple primary key. There are no Word like "Primary Keys". You can create a Primary Key only by one or more field/s. As per Your situation You have multiple Primary Key on table, then you can use Unique Key by uncheck the Allow Nulls. It will work like primary key. They can be created multiple . For more knowledge about keys you can refer below articles : https://www.c-sharpcorner.com/article/find-primary-unique-foreign-keys-and-delete-them/ https://www.c-sharpcorner.com/article/add-primaryuniqueforeign-keys-and-delete-them-in-sql/

Jignesh Kumar · Answer

@Amit Gupta, We can create for multiple column but pk will be only one. We can not create more than one primary key per Table.

Jignesh Kumar · Answer

Hi Pramod, No we can not create more than one primary key for table. Only one PK for table.

Udit Chauhan · Answer

No, we can not have more than one primary key in table. if you want to make uniqueness of records then you can make multiple columns together as composite key.

Purvi Barot · Answer

A primary key is a field in a table which uniquely identifies each row/record in a database table. Primary keys must contain unique values. A primary key column cannot have NULL values. A table can have only one primary key, which may consist of single or multiple fields. When multiple fields are used as a primary key, they are called a composite key. If a table has a primary key defined on any field(s), then you cannot have two records having the same value of that field(s). Thank you!

Shahriar Nikkhah · Answer

You can creat 2 UNIQUE KEYs, each UK and have multiple fields

Jenith Thakkar · Answer

Primary Key: There can only be one primary key in a table In some DBMS it cannot be NULL - e.g. MySQL adds NOT NULL Primary Key is a unique key identifier of the record Unique Key: Can be more than one unique key in one table Unique key can have NULL values It can be a candidate key Unique key can be NULL and may not be unique

Md Sarfaraj · Answer

You can not uses

Vinay Kumar Dara · Answer

No ! but as a combination of two columns we called Composite key. Student Table: As a combination of RollNo and Branch columns only Student table can get the result. RollNo Branch Rank# 1 ECE 22 2 ECE 4 1 CSE 12

Salman Beg · Answer

No, We can not create more than one primary key in a table.

Rajeesh Menoth · Answer

Hi, Only one !! The PRIMARY KEY constraint uniquely identifies each record in a table. Primary keys must contain UNIQUE values, and cannot contain NULL values. Reference : https://www.w3schools.com/sql/sql_primarykey.asp

Ravi Patel · Answer

A table can have only one primary key , which may consist of single or multiplefields. When multiple fields are used as a primary key, they are called a compositekey