calculated field and update 
Author Message
 calculated field and update

 I'm using a datagrid to show data from a table that has a date field. I
wanted an extra column on the datagrid to show a character that would
flag Saturdays, Sundays, or both, as a visual aid to seeing the data
grouped in weeks.
 I couldn't find a way to set a datagrid column to some separate value
calculated per record, once the datagrid had its datasource set to the
 The solution I came up with was to modify the query statement to
include a calculated field, like this:

SELECT * , iif ((date mod 7 >-1 and date mod 7 < 2),'?','') AS wknd FROM

where date is one of the fields included in runs. Then I added a first
column to the datagrid with datafield = "wknd". This works ok, in that
it shows an extra column with a character '?' if the day is Saturday or
Sunday, and nothing if it isn't.

 Fine so far, but then, if I change a field in that recordset, and try
to update it, I get an error message:
"Row cannot be located for updating. Some values may have changed since
it was last read."

 I supposed this was due to the inclusion of a calculated field in the
recordset, and I got around it by doing edits/updates with a second
recordset, which then had to be synchronized to the first recordset.

 Is it correct that a recordset that includes a calculated field can't
be used for edits/updates? If there is a way around it, what is it?

 Does anyone know a way to make a datagrid column show a calculated
value based on its row's contents without making it part of the

 Is there some format string that could produce a flag for particular
weekdays in a redundant column set to the field 'date'?

 Thanks for any ideas.


Thu, 30 Sep 2004 10:12:44 GMT  
 calculated field and update

Try MSFLEXGRID. More code but more control.


Thu, 30 Sep 2004 21:27:53 GMT  
 [ 2 post ] 

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