Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Access query - First keyword question

Posted on 2013-06-02
7
Medium Priority
?
421 Views
Last Modified: 2013-06-02
Dear experts -
I have a table of milestones for each milestone of a project. I want to determine the EARLIEST INCOMPLETE record in this table.
What I've done so far:
Create a Subquery, sorting the results by project + date + descriptor.
I created a master query that invokes the subquery and uses the FIRST keyword to find the first occurrence for this project_ID. (I assumed that it was using the sort order built into the subquery.)
It is simply pulling the wrong information.
Any ideas?
Thanks!
0
Comment
Question by:terpsichore
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 3
7 Comments
 
LVL 38

Accepted Solution

by:
Jim P. earned 2000 total points
ID: 39214455
You'll need to add an autonumber column to the table like ID.

Then you query will  look something like this:

SELECT SubQ.project, SubQ.datefld, SubQ.descriptor
FROM (SELECT TableX.project, TableX.datefld, TableX.descriptor,  (select count(*) from tableX as x where x.project=tablex.project and x.datefld=tablex.datefld and x.ID<=tablex.ID) AS Seq
   FROM TableX
   WHERE descriptor = "Incomplete"
   ORDER BY TableX.project, TableX.datefld, TableX.descriptor, TableX.ID) SubQ
WHERE SubQ.Seq = 1

Open in new window

0
 

Author Comment

by:terpsichore
ID: 39214485
thanks - can you explain this a little more, and why this would work and why my version wouldn't, perhaps? THANK YOU
0
 
LVL 38

Expert Comment

by:Jim P.
ID: 39214518
Basically I'm creating a sequence number. And it is a good idea to learn how to do it as the First and Last keywords are unique to Access/JET SQL and nothing else.

I presume that the data is added to you table at random times. This puts them in order and only select the sequence number 1.

That is based on the idea you have an index on the project and datefld when you add the autonumber.
0
TCP/IP Network Protocol Cheat Sheet

TCP/IP is a set of network protocols which is best known for connecting the machines that make up the Internet. The truth is that TCP/IP is one of the oldest network protocols and its survival is mainly based on its simplicity and universality.

 

Author Comment

by:terpsichore
ID: 39214525
great - sorry to trouble, but one last question before i award you the points - we are migrating to sql server (and also need a consultant for that!) - should we use a different query? THANK YOU
0
 
LVL 38

Expert Comment

by:Jim P.
ID: 39214545
should we use a different query?

It is easier in MS SQL.

To get a sequence number you use the Row_Number or  Rank functions.
0
 

Author Closing Comment

by:terpsichore
ID: 39214617
Very perceptive, very thorough.
0
 
LVL 38

Expert Comment

by:Jim P.
ID: 39214812
Thanks.

Glad to be of assistance. May your days get brighter and brighter.
0

Featured Post

Enroll in September's Course of the Month

This month’s featured course covers 16 hours of training in installation, management, and deployment of VMware vSphere virtualization environments. It's free for Premium Members, Team Accounts, and Qualified Experts!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In part one, we reviewed the prerequisites required for installing SQL Server vNext. In this part we will explore how to install Microsoft's SQL Server on Ubuntu 16.04.
It is possible to export the data of a SQL Table in SSMS and generate INSERT statements. It's neatly tucked away in the generate scripts option of a database.
In Microsoft Access, learn different ways of passing a string value within a string argument. Also learn what a “Type Mis-match” error is about.
Add bar graphs to Access queries using Unicode block characters. Graphs appear on every record in the color you want. Give life to numbers. Hopes this gives you ideas on visualizing your data in new ways ~ Create a calculated field in a query: …

722 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question