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SQL Joins with Paradox

SQL Joins with Paradox

Question:
I’m developing a program that lists all of a shop’s clients and the items that they purchased. The problem is that if some clients haven’t bought anything, they don’t appear. I would like to perform a left join (like in Access) with Paradox. However, I don’t know Paradox and the BDE well enough. Can you please help me?

Answer:
Paradox and the BDE use a subset of ANSI SQL called LocalSQL. However, I should note that after Delphi 3, the BDE is completely ANSI SQL compliant. To do a left outer join on two tables, you’d do something like this:

SELECT D.ClientID, D.ClientName , D1.*FROM "TABLE1.DB" D LEFT OUTER JOIN "TABLE2.DB" D1 WHERE (D1.ClientID = D.ClientID)

That’s it! It’s more of syntactical thing than anything else.

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