Why does Access duplicate records when appending to another table

[rlvarga0624]

The issue that I have is that Access 10 duplicates records when I try to append them from one table to another. the tables have identical naming conventions, and attributes.

This is the code that Access provides:

INSERT INTO TblWODDate
SELECT TblTempInput1.*
FROM TblTempInput1 LEFT JOIN TblWODDate ON (TblTempInput1.Date = TblWODDate.Date) AND (TblTempInput1.Movements = TblWODDate.Movements);

Thanks for your help
bob

[PhilOfWalton]

Basically Bob, You have told Access to add the records and for once in a while Access does as it is told.

If you want to prevent duplicates, you must set up the table's indexes correctly. I presume you want to prevent the duplication of Date & Movement, so try creating a new Index Called DateMovement based on Date & Movement and make it Unique.

NB "Date" is a reserved word and should NEVER be used as a field name. Change it to MovementDate or something similar. Another NoNo is "Name" and there are lots more.

Phil