insert field if exists or add new row - guidance needed please

[sjk1000]

Hi All

I'm looking to update a table in a database based on the input to the form in the screenshot attached. It's a web portal with multiple stores potentially selling the same product. All the products are on the database. If a seller chooses to sell something, they enter the quantity and price details in the web front-end I've created.

 

I figure the logic for what I'm trying to do would be

 

IF SellerID AND Product ID exists then update the relevant field (ie they're just changing the details of a product they're already selling)

 

ELSE

 

INSERT a new row for that seller with the seller-specific details of the product.

 

I've attached a screenshot of my seller_stock table.

 

From my background reading It feels like I could use an INSERT ON DUPLICATE but that works with keys doesn't it? The alternative I think is to write the IF ELSE above. Is there a funciton that does what I'm looking for?

Any help would be very much appreciated

Thanks, Steve

 

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[gevans]

try looking up REPLACE instead of using INSERT and UPDATE

[revraz]

Just base it on if any rows are returned.  If so, update, if not insert.

[sjk1000]

Thanks for the quick response guys. I'll update the thread with the solution when I get to it. If I forget and someone's interested in the script feel free to drop me a reminder by Private Message.

Cheers, Steve