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Need Some Help with a join Query

Gregg Bolinger
GenRocket Founder
Ranch Hand

Joined: Jul 11, 2001
Posts: 15299
    
    6

I have the following:



I need to write a query such that I find all the header rows that contain details with 2 specific products. I have the following so far:



This isn't getting what I expect. I want header rows with at least 2 detail rows. Of those 2, each one should point to the product IDs I am specifying.

Thanks.


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Paul Clapham
Bartender

Joined: Oct 14, 2005
Posts: 18650
    
    8

Does the answer have to involve joins? Because I would do something like this:


I'm sure that code could be recast in terms of joins, but I wouldn't because I find it more readable the way I wrote it.
Gaurangkumar Khalasi
Ranch Hand

Joined: Jun 02, 2012
Posts: 187
Gregg Bolinger wrote:I want header rows with at least 2 detail rows. Of those 2, each one should point to the product IDs I am specifying.

You can add "group by header.id having count(detail.header_id)>=2" at the end of your query...May you get your answer???...
Martin Vajsar
Sheriff

Joined: Aug 22, 2010
Posts: 3610
    
  60

My take on it with joins (the table needs to be joined twice):

For simplicity I've omitted the join to the products table. Assuming the transaction_detail does not contain product_ids which would not be present in the products table, that join is not necessary (won't eliminate any rows).

(Hope I didn't get it wrong...)
 
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