SQL: Violation of primary key constraint found duplicate key value

Scenario: we are inserting a value in our table that has a primary key constraint enabled. While inserting, we get an error: "Violation of primary key constraint 'xyz'. Cannot insert duplicate key in object 'dbo.customertbl'. The duplicate key value is (4).

Resolution: The error says that the value you are inserting in your primary key enabled column is already present in the column. Select your table and search for the value listed in your error "duplicate key value is (value)". 

You have two options:

• Delete the value from the table (not recommended)
• Check why the duplicate value is coming from the source query that you are inserting into this table?.
•  Most likely, you might have to either alter your primary key and make it a composite key (multiple columns) or see maybe the data fetching query is not functioning properly (fix the query)