Change records as a group using an update query
1 Create a query, selecting the tables or queries that include the records you want to update and the fields you want to use for setting criteria.
2 In query Design view, click the arrow next to Query Type on the toolbar, and then click Update Query.
3 Drag from the field list to the query design grid the fields you want to update or you want to specify criteria for.
4 In the Criteria cell, specify the criteria if necessary.
5 In the Update To cell for the fields you want to update, type the expression or value you want to use to change the fields.