Hello everyone
Suppose a table named tbl_med.
The tbl_med table has six fields: [nom_lab], [nom_desc], [nom_apres], [data_vigencia], [cod_med], [vr_pmc].
I want a SQL query to find duplicated records in relation to these fields: [nom_lab], [nom_desc], [nom_apres], [data_vigencia].
But besides this I want that query SHOWS ALL THE SIX FIELDS (not only the four ones referenced above).
Access 2007 Help has created the following SQL query to solve this question:
SELECT tbl_med.[nom_lab], tbl_med.[nom_desc], tbl_med.[nom_apres], tbl_med.[data_vigencia], tbl_med.[cod_med], tbl_med.[vr_pmc]
FROM tbl_med
WHERE tbl_med.[nom_lab] IN (SELECT [nom_lab] FROM [tbl_med] As Tmp GROUP BY [nom_lab],[nom_desc],[nom_apres],[data_vigencia] HAVING Count(*)>1 And [nom_desc] = [tbl_med].[nom_desc] And [nom_apres] = [tbl_med].[nom_apres] And [data_vigencia] = [tbl_med].[data_vigencia])
ORDER BY tbl_med.[nom_lab], tbl_med.[nom_desc], tbl_med.[nom_apres], tbl_med.[data_vigencia];
Could anyone explain how this SQL query work?
Does anyone have a more intuitive query (and easier to understand)?
Thank you in advance.
Tidak ada komentar:
Posting Komentar