Solved

SQL delete query for duplicate records in Access

Posted on 2008-10-31
9
1,277 Views
Last Modified: 2012-05-05
This is a follow up question to an earlier question.  I have an Access database with duplicate records.  The key is a composite of FUND, GROUP, ID.  How would I write a query to delete duplicate records in the table.
0
Comment
Question by:VBStudent
  • 2
  • 2
  • 2
  • +2
9 Comments
 
LVL 12

Expert Comment

by:jazzIIIlove
ID: 22852809
Hi there;

DELETE FROM our_table WHERE rowid not in(SELECT MIN(rowid) FROM our_tabl eGROUP BY column1, column2, column3... ;

Here column1, column2, column3 constitute the identifying key for each record.

Best regards...
0
 

Author Comment

by:VBStudent
ID: 22853306
it doesn't appear as though rowid is recognized in Access.  Any other suggestions?
0
 
LVL 7

Expert Comment

by:UniqueData
ID: 22853830
don't award any points to me, just thought I would help out...

rowid is probably referring to a unique record id, usually an AutoNumber field.  I know you have the three fields that make up the key, but do you also have (or can you add) an AutoNumber?

Michael
0
Master Your Team's Linux and Cloud Stack

Come see why top tech companies like Mailchimp and Media Temple use Linux Academy to build their employee training programs.

 
LVL 9

Expert Comment

by:jamesgu
ID: 22855495
delete from <table>
inner join ( select FUND, GROUP, ID from <table> group by FUND, GROUP, ID having count(*) > 1) b on
<table>.FUND = a.FUND
<table>.GROUP = GROUP
<table>.ID = a.ID



0
 
LVL 9

Accepted Solution

by:
jamesgu earned 500 total points
ID: 22855516
delete from <table>
from <table>
inner join ( select FUND, GROUP, ID from <table> group by FUND, GROUP, ID having count(*) > 1) b on
<table>.FUND = a.FUND
<table>.GROUP = GROUP
<table>.ID = a.ID

--missed a from clause
0
 
LVL 12

Expert Comment

by:jazzIIIlove
ID: 22856258
yes...rowId is autoNumbered field of yours...
0
 

Author Closing Comment

by:VBStudent
ID: 31512146
Thank you for your help
0
 

Expert Comment

by:sarcharan
ID: 23681243
I thank all of you for helping me. I found one more document to be quite interesting.

delete from t1 where tl.rowid >(select min(tl2.rowID) from t1 tl2 where tl.col1 = tl2.col1 and tl.col2 = tl2.col2)
====================
sp_rename 'dup_authors', 'temp_dup_authors'

select distinct *
into dup_authors
from temp_dup_authors

drop table temp_dup_authors
Deleting-Duplicate-Records.doc
0
 

Expert Comment

by:sarcharan
ID: 23681269
0

Featured Post

Use Case: Protecting a Hybrid Cloud Infrastructure

Microsoft Azure is rapidly becoming the norm in dynamic IT environments. This document describes the challenges that organizations face when protecting data in a hybrid cloud IT environment and presents a use case to demonstrate how Acronis Backup protects all data.

Question has a verified solution.

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

Experts-Exchange is a great place to come for help with solutions for your database issues, and many problems are resolved within minutes of being posted.  Others take a little more time and effort and often providing a sample database is very helpf…
Overview: This article:       (a) explains one principle method to cross-reference invoice items in Quickbooks®       (b) explores the reasons one might need to cross-reference invoice items       (c) provides a sample process for creating a M…
In Microsoft Access, learn how to use Dlookup and other domain aggregate functions and one method of specifying a string value within a string. Specify the first argument, which is the expression to be returned: Specify the second argument, which …
With Microsoft Access, learn how to specify relationships between tables and set various options on the relationship. Add the tables: Create the relationship: Decide if you’re going to set referential integrity: Decide if you want cascade upda…

770 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