joins - PostgreSQL Database

Hi every one

Pl look into the situation

Tables
Product(maker, model, type)
PC(code, model, speed, ram, hd, cd, price)
Laptop(code, model, speed, ram, hd, screen, price)
Printer(code, model, color, type, price)

requirement:

Define the maximal price of PC produced by each maker.
Result set: maker, maximal price.

thanks in advance

Mar 15 '07 #1

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2432

michaelb

534

Expert 512MB

The two links below should give you everything you need to write this query.

Table Expressions

Joins between Tables

Mar 15 '07 #2

gazeatvara

The two links below should give you everything you need to write this query.

Table Expressions

Joins between Tables

Hi michale

wats wrong with this

select maker,max(price) from product natural join pc group by 1;

Mar 15 '07 #3

michaelb

534

Expert 512MB

Your requiremens says:
Define the maximal price of PC produced by each maker.
but you are joining tables on model.

It seems you need to work on your schema....
Table PC, for example has no field that can be used to identify a maker.

Mar 16 '07 #4

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