Title: Message

Thank you for the explanation …

 

Best Regards,

Eric

 

Eric Tishler

Software Architect

Resolute Partners, LLC

Phone: 203.271.1122

Fax: 203.271.1460

[EMAIL PROTECTED]

 

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]On Behalf Of Paul Ritchie
Sent: Friday, March 19, 2004 4:15 PM
To: NZ Borland Developers Group - DelphiList
Subject: Re: [DUG] Programming in Delphi, but have a SQL question

 

The LEFT OUTER JOIN returns rows in the Subset table that have no corresponding row in the Master table.  Such rows are indicated by a indicated by a NULL Master.ID column.

 

So specifying WHERE Master.ID IS NULL isolates only these rows. 

 

NB This assumes the ID column is not nullable, which is usually the case with primary/foreign keys used to perform such joins.

 

cheers,

Paul.

----- Original Message -----

To: [EMAIL PROTECTED] ; NZ Borland Developers Group - DelphiList

Sent: Saturday, March 20, 2004 6:09 AM

Subject: RE: [DUG] Programming in Delphi, but have a SQL question

 

What if the JOINed master column is not null? …

 

 

Eric Tishler

Software Architect

Resolute Partners, LLC

Phone: 203.271.1122

Fax: 203.271.1460

[EMAIL PROTECTED]

 

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]On Behalf Of Paul Ritchie
Sent: Thursday, March 18, 2004 4:17 PM
To: 'NZ Borland Developers Group - Delphi List'
Subject: RE: [DUG] Programming in Delphi, but have a SQL question

 

I would tend to use an outer join where the JOINed master column is NULL eg

 

SELECT Subset.*

FROM Subset

LEFT OUTER JOIN Master ON Subset.ID = Master.ID

WHERE Master.ID IS NULL

 

cheers,

Paul.

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]On Behalf Of Eric Tishler
Sent: Friday, 19 March 2004 9:46 a.m.
To: NZ Borland Developers Group - Delphi List
Subject: [DUG] Programming in Delphi, but have a SQL question

I am trying to implement a new report in Delphi, but I am having problems with the query. I know this is not a straight Delphi question, but I was hoping someone here could steer me in the right direction.

 

I have two tables with transactions. One table contains ALL transactions, the second table is a subset of the first with only a specific set of transactions. The columns differ between the two tables, but there is enough relational information for me to match all of the subset transactions with the master transaction table.

In some odd cases the subset transaction is inserted, but the corresponding entry is not added to the master transaction table.

I need to write a query that shows which transactions in the subset table do not appear in the master table.

Can someone help me with this?

Thanks,

Eric

 

 

Eric Tishler

Software Architect

Resolute Partners, LLC

Phone: 203.271.1122

Fax: 203.271.1460

[EMAIL PROTECTED]

 

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