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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.
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.
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).
4 Answers. Sorted by: 12. In your case these fields are natural key. Surrogate Key: Surrogate keys are keys that have no “business” meaning and are solely used to identify a record in the table.
23 Μαρ 2019 · A multi-column key for a clustered table helps with scanning on parts (or all) of the columns. It also allows a purely index based access if it is covering. Since batchid is the first column you can access by that.
23 Μαΐ 2012 · A table can have have only one primary key. Consider using two unique indexes. CREATE UNIQUE INDEX index1 ON Table(column1); CREATE UNIQUE INDEX index2 ON Table(column2);
