A call to all SQL Query wizards!!

[kieranharrison]

Hi Guys,

Just wondering if anyone could please help me re-write this query. Currently the query results will show a row only if all of the fields in the query are populated - this is a problem for me because the query is pulling from different tables which might not always be populated.

Basically, I need the query to show 'null' or something like that if there is no value in the field, rather than not show the entire row at all.

Hope that makes sense.

SELECT received_files_table.Processing_Month AS ProcessingMonth, received_files_table.IATA_Code AS IATACode, received_files_table.Airline AS Airline, received_files_table.Received_Date AS ReceivedDate, received_files_table.Received_Notes AS ReceivedNotes, uploaded_files_table.IATA_Code AS UploadedIATA, uploaded_files_table.Airline AS UploadedAirline, uploaded_files_table.Uploaded_Date AS UploadedDate, to_publish_table.Published_Month AS PublishedMonth, to_publish_table.IATA_Code AS PublishedIATA, to_publish_table.Published_Date AS PublishedDate
FROM received_files_table, uploaded_files_table, to_publish_table;

Thanks very much in advance!

[June7]

There is no JOIN clause. This is a cross join or Cartesian relationship. Every record of each table will associate with every record of the other tables. This can result in a very large, very slow dataset. I doubt you will like the result.

Should to_publish_table have Airline and Notes fields?

How should these tables be related? Link on the common Processing_Month, IATA_Code, Airline fields?

Why not have 1 table with another field for category (received, uploaded, published)? Or a field for each category date?

[orange]

Here is the original sql from post #1 reformatted for readability

SELECT received_files_table.Processing_Month AS ProcessingMonth
	,received_files_table.IATA_Code AS IATACode
	,received_files_table.Airline AS Airline
	,received_files_table.Received_Date AS ReceivedDate
	,received_files_table.Received_Notes AS ReceivedNotes
	,uploaded_files_table.IATA_Code AS UploadedIATA
	,uploaded_files_table.Airline AS UploadedAirline
	,uploaded_files_table.Uploaded_Date AS UploadedDate
	,to_publish_table.Published_Month AS PublishedMonth
	,to_publish_table.IATA_Code AS PublishedIATA
	,to_publish_table.Published_Date AS PublishedDate
FROM received_files_table
	,uploaded_files_table
	,to_publish_table

Further to June's comment, we really need to know the "business" behind this SQL in order to know what is being requested in simple, plain terms.