How to Update a Table in Microsoft Access Using an Inner Join?

Updating from an Inner Join in SQL

To update a table using data retrieved from an inner join in Microsoft Access, modify the SQL statement to follow these principles:

Removing Unnecessary Clauses:
The SELECT and ORDER BY clauses are not required when updating from a join.

Joining Tables:
Use an INNER JOIN to establish a relationship between the tables involved in the update.

Identifying the Target Table:
Specify the table that you want to update, using the UPDATE keyword.

Setting Column Values:
Use the SET keyword to assign values to specific columns in the target table. The values can be derived from the joined tables using proper aliases.

Example:

To update the FermentId column in the EXAMPLETABLE table based on the result of an inner join between FERMENT and [BELGIUM BEER], you would use the following SQL statement:

UPDATE EXAMPLETABLE
INNER JOIN (
  SELECT
    FERMENT.FermentId
  FROM
    FERMENT
  INNER JOIN
    [BELGIUM BEER]
  ON
    FERMENT.FermentName = [BELGIUM BEER].FermentId
) AS a
ON
  EXAMPLETABLE.SomeColumn = a.FermentId
SET
  EXAMPLETABLE.FermentId = a.FermentId;

Note: Replace SomeColumn with the column in the EXAMPLETABLE table that you want to match with FermentId.

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