Query from two tables, add and edit do not work

[David Drosselmeyer]

I have a database with several tables. I have created a query that pulls all
fields from two tables joined by three fields (ID, Year, Month) which are
common to both tables. My query gets the records I want, but I am not able
to edit the field contents or add any new records.

Any suggestions on what I am doing wrong?

Thanks for your help.
David

 

[Duane Hookom]

Are ID, Year, and Month defined as the Primary Key in one or both tables?

 

[David Drosselmeyer]

No, there are no primary keys in either table. The "left" table has many
records and the "right" table has only a few records.

Most of the tables in the database are accessed by a commercial program and
won't tolerate changes to the database structure. The "right" table was
added to the database by me and I can alter it in any way necessary.

Thanks,
David

ps. sorry for the off group email, I pressed the wrong reply button.

 

[Duane Hookom]

If you can't make a primary key in either table then create a main form of
the form with a few records and subform of the many records. Set the Link
Parent/Child properties to your common fields.