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Creating A Calculated Column In MS SQL

This is something I’ve been doing a lot lately.
Seem to find myself googling for the syntax every time I have to so this is a reference for me, mostly, but you can use it if you behave.

The T-SQL syntax for adding a calculated column to a table looks like this:

ALTER TABLE [<TableName>]
ADD <NewCalculatedColumnName> AS (<SQL for value>) PERSISTED

A couple of notes:

  • <TableName> is the  name of the table you’re adding a column to.
  • <NewCalculatedColumnName> is the name of the new column
  • <SQL for value> is a valid T-SQL statement.
  • PERSISTED – Specifies that the Database Engine will physically store the computed values in the table, and update the values when any other columns on which the computed column depends are updated.