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If you're asking if a table can have multiple columns as a primary key, then for MS SQL Server, the answer is yes, and it's called a composite (corrected) key.
I have a table with four columns that are all non-nullable, and the data is such that all four are needed to distinguish a unique record. This means that if I were to make a primary key, it would need to comprise all columns.
A primary key is a column or a group of columns that uniquely identifies each row in a table. You create a primary key for a table by using the PRIMARY KEY constraint. If the primary key consists of only one column, you can define use PRIMARY KEY constraint as a column constraint: pk_column data_type PRIMARY KEY, ...
22 Φεβ 2022 · Create Primary Key on Multiple Columns in SQL Server. In our examples, we created Primary Keys on single columns. If we want to create Primary keys on multiple columns, we need a different syntax. To add multiple columns as part of the Primary Key, we need to simply add comma-separated values of the column names that should be part of the ...
4 Οκτ 2021 · A primary key is a constraint put on a column or columns in a table to guarantee each row in a table is unique. One aspect that makes a table relational is that it has unique rows. If there are two rows in a table with exactly the same data, that table is not considered relational.
Operation. A PRIMARY KEY can be defined on a column or multiple columns while creating a table or later. It is also possible to drop a PRIMARY KEY in a table if not required. SQL Server PRIMARY KEY Syntax.
10 Σεπ 2011 · The first common option is to define an integer column as a primary key. You can have your application assign a value or you can assign an identity property to the integer column (i.e. int identity (1,1)) and let SQL Server generate the value for you (which is my preference).
