mysql - SQL Pricing Tiers -


i have pricing lookup table in mysql need lookup right pricing based on transaction quantity.

say example, have pricing table pricing, looks like:

product    quantity    price prod1      1           4 prod1      10          3 prod1      100         2 prod1      1000        1 prod2      1           0.4 ...

and have table called transaction contains sales data: 

product    sales  prod1      144 prod2      2 ...

how can sales multiply right unit price based on quantity. likes: 

product    sales    quantity    unitprice prod1      144      100         2 prod2....

i tried join 2 table on product don't know go there, thanks!

one way price using correlated subquery:

select t.*,        (select p.price          pricing p         p.product = t.product , p.quantity >= t.quantity         order p.quantity         limit 1        ) price transaction t;

a similar subquery can used other information such pricing tier.

for performance, want index on pricing(product, quantity).


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