Using openbravoPOS i got a mySQL database of all my producs tickets stock etc.
Products are in one table and the tickets are in another, so to make a开发者_StackOverflow query that get me all the products that are sold (and therefore are in ticketlines) are simple.
How do I make a query that gives me the products that are not i any ticketlines?
You can use a LEFT OUTER JOIN
for this:
select p.*
from products p
left outer join tickets t on p.ProductID = t.ProductID
where t.ProductID is null
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