need help

  • Thread starter Thread starter ferio
  • Start date Start date
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ferio

hi,

i just started to learn access to do my project.i have few
questions need to clarify:

1.do we get same return if we set parameter in criteria
instead of place it on field row on query?
ex:
case1: query field>> sum:sum criteria: m+n
case2: query fiels>> sum: m+n criteria: blank

2.query has five fields say a,b,c,d and e.we get records
from tables and assigned it to field a and b.field
c=a+b.field d=c*a and field e=sum d. question is do we get
updated records for field d and e each time add records?

3.a table consist of 100 rows(and few coloums).now i
create query such that it collects all data from certain
row.what command should i use for its criteria?

cheers,
ferio
 
Hi,


1. No. I assume you use the grid of the query designer. If there is no
criteria, the "expression" is not filtered. If there is a criteria, only the
records where the expression is (here, equal) to the supplied value will be
kept.

2. No, unless you use a query (or, with MS SQL Server, a computed column,
which seems to be based on a view behind the scene). Well, if you use an
aggregate, like SUM, which add the expression over all the rows for a given
group, that query is not updateable, to start with, so, you won't be able to
even add a new row. If you use just arithmetic, the computed columns should
be updated in a FORM based on a query, as soon as you move out of the new
record, or as you save the record.

3. Which row? Your answer should be in terms of data known by the database
engine. You cannot tell, "those Houdini selected mentally", neither "the
six first ones actually displayed on the screen". You have to come with
"DATA", like, those with a value, under DateTime field, between #1-1-2001#
and #1-1-2002#, as example. The "position" of the record is NOT part of the
data stored in the record and cannot be directly used as part of the
criteria.



Hoping it may help,
Vanderghast, Access MVP
 
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