Unique values limiting memo field to 256 chars?

[Max Moor]

Hi All,
I just noticed some data missing off the end of a memo field returned
by a query with Unique Values set True. It looks like the number of
characters was cut off after 256. Am I doing something wrong somewhere
else, or is this expected behavior?!?!

- Max

 

[Allen Browne]

That is correct. Access returns only the first 255 characters if it is
forced to do any aggregation on the memo field.

Could you use a Totals query to group by the fields you really want to
de-dupe, and then use First in the total row under the memo field? That way
Access is free to return the entire memo field.

 

[Van T. Dinh]

This is an expected behaviour and JET truncates after 255 characters.

If Unique Values is set to True, JET needs to compare the String values in
the Memo Field. For efficiency, JET is implement to truncate Memo Field
values to 255 characters and then compare the truncated values.

 

[Max Moor]

This is an expected behaviour and JET truncates after 255 characters.

If Unique Values is set to True, JET needs to compare the String
values in the Memo Field. For efficiency, JET is implement to
truncate Memo Field values to 255 characters and then compare the
truncated values.

Thanks guys. At least I understand why. Fortunately, as I reviewed the
query's application, it occurred to me that there was no good reason to
have a unique values query anyway, so it eneded up not being an issue. It
was good to learn something new, though.
TTFN