Step 1: Create a select query to identify the records to update Assign the name of the original version to the backup copy, and then open the renamed backup copy in Access. To revert to a backup, close and rename the original file so that the backup copy can use the name of the original version. In the Save Backup As dialog box, specify a name and location for the backup copy, and then click Save.Īccess closes the original file, creates a backup, and then reopens the original file. On the right, under Advanced, click Back Up Database. Note, if you're using Access 2010, click the File tab, and then click Save & Publish.
You cannot undo the results of an update query, and making a backup helps make sure that you can reverse your changes if you change your mind.Ĭlick the File Tab, and then click Save As. Tip: Back up your database before you run an update query.
Because some duplicate records are removed from the results, Access cannot update all the necessary records.įields that are primary keys In some cases, such as if the primary key field is used in a table relationship, you cannot update the field by using a query unless you first set the relationship to automatically cascade updates. This restriction applies whether you use an update query or try to update data manually by entering values in a form or a datasheet.įields in a union query You cannot update data from fields in a union query because each record that appears in two or more data sources only appears once in the union query result. The update operation is not possible because it is not possible to determine what records were excluded as duplicates, and therefore not possible to update all the necessary records. Some of the values represent a single record, and others represent more than one record. Because calculated fields do not have a permanent storage location, you cannot update them.įields from a totals query or a crosstab query The values in these types of query are calculated, and therefore cannot be updated by an update query.ĪutoNumber fields By design, the values in AutoNumber fields change only when you add a record to a table.įields in unique-values queries and unique-records queries The values in such queries are summarized. They only exist in your computer's temporary memory after Access calculates them. Restrictions on fields that can be updatedĪn update query cannot be used to update data in the following types of fields:Ĭalculated fields The values in calculated fields do not permanently reside in tables.
Use criteria that do not depend on the value that you want to replace.Ĭhange records in more than one table at the same time. Unlike the Find and Replace dialog box, an update query lets you: Like the Find and Replace dialog box, an update query lets you specify which value is being replaced, and what the new value is. Here are the similarities and differences between Find and Replace and an update query: To add new records to a database you use an append query, and to delete whole records from a database you use a delete query. You cannot use an update query to add new records to a database, or to delete records from a database. You can think of update queries as a powerful form of the Find and Replace dialog box. You use update queries in Access databases to add, change, or delete the information in an existing record. Access for Microsoft 365 Access 2021 Access 2019 Access 2016 Access 2013 Access 2010 Access 2007 More.
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