Updating a Fieldd by using UPDATE statement

Hi,
Is it, or not, possible to use a UPDATE statement?
Every new month I have to change some fieldcontent (Period) .
In Access I did this by using UDATE SET “Period” = (number of the mont (01-12)
However I get a SQL syntax error.

                "De gegeven opdracht is geen SELECT-instructie.
                 Alleen query's zijn toegestaan.

How can I achieve this?

Tools > SQL > Run SQL command directly

UPDATE "TheTable" SET "Period" = 5

Query editor could only be used for queries (SELECT …), not for UPDATE, INSERT
.
If there is the same content in many rows of a table the better solution is to get this content from another table by foreignkey. So you have only to switch the value in the other table.

RobertG,
Thanks again for your reply.
You are right, to create an other “Period” table, however it goes well by the solution from CRDF.
It are not that many rows to update.

Ron