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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.
18 Αυγ 2019 · A composite primary key is a primary key consisting of multiple columns. Microsoft usually refers to these as multicolumn primary keys in its documentation. This article provides an example of creating a composite primary key using Transact-SQL in SQL Server.
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, ...
The PRIMARY KEY constraint uniquely identifies each record in a table. Primary keys must contain UNIQUE values, and cannot contain NULL values. A table can have only ONE primary key; and in the table, this primary key can consist of single or multiple columns (fields).
This means that if I were to make a primary key, it would need to comprise all columns. Queries against the table will almost always be to pull back a single record, i.e. all columns will be filtered in the query.
22 Φεβ 2022 · Create Primary Key on Multiple Columns in SQL Server. Primary Key During the Table Creation. Primary Key After the Table Creation. Drop the Primary Key in SQL Server. Modify the Primary Key. Disable/Enable Primary Key. The Myths about the Primary Key. Table with Primary Key is not a Heap Table.
18 Απρ 2024 · In Table Designer, select the row selector for the database column you want to define as the primary key. If you want to select multiple columns, hold down the CTRL key while you select the row selectors for the other columns. Right-click the row selector for the column and select Set Primary Key.
