Subtract one table from another (difference)

[davelarue]

Hello,
What is the simplest way to subtract the contents of table A from table B? One of the columns of table A contain duplicated entries of a column in table B.
What i want is the opposite of:
"Only include rows where the joined fields from both tables are equal"

Thank you.

David

 

[MStef]

If you are sure that it is duplicated, you don't need to make SUBTRACT.
Make an UPDATE the field in the table A, with the value in the same field in the table B. LinK thise two tables with JOINED FIELDS.
UPDATE QUERY.
Before take a copy of table A.

 

[neileg]

Not clear what you want. Maybe the unmatched query wizard will do what you want.

 

[davelarue]

To make things clear, i made an example.

Column B represents the data which are same for both tables. The right table has 1500 entries, left table has 500 entries (which are duplicates in right table). I want the result to be right table with 1000 unique records...

 

[neileg]

Then the unmatched query wizard is exactly what you need.