Re: Help on SQL query
От | Ian Tan |
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Тема | Re: Help on SQL query |
Дата | |
Msg-id | CAAj7RQ85Jxa2U3Tya4=2v9cUDN1HQEuGoAsN_Ef7YTcB+tWj4w@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: Help on SQL query (Rob Sargent <robjsargent@gmail.com>) |
Ответы |
Re: Help on SQL query
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Список | pgsql-sql |
Hello Andrew, Thank you, I appreciate your response and your help. Hello Rob, I learn in my own time and had no one to ask. If pgsql-sql is not the correct forum for these kinds of question, kindly let me know. Thank you. Regards, Ian On Fri, 15 Feb 2019 at 17:38, Rob Sargent <robjsargent@gmail.com> wrote: > > > > > On Feb 15, 2019, at 10:28 AM, Andrew Gierth <andrew@tao11.riddles.org.uk> wrote: > > > >>>>>> "Ian" == Ian Tan <iantan1268@gmail.com> writes: > > > > Ian> How do I write an SQL query so that the "name" text in car_parts > > Ian> are added to the bill_of_materials table, so that it looks like > > Ian> this: > > > > The only trick with this is that you need to join the car_parts table > > twice (once for parent and once for child), and to do that you need to > > give it different alias names: > > > > select bom.parent_id, > > ppart.name as parent_name, > > bom.child_id, > > cpart.name as child_name > > from bill_of_materials bom > > join car_parts ppart on (ppart.id=bom.parent_id) > > join car_parts cpart on (cpart.id=bom.child_id); > > > > -- > > Andrew (irc:RhodiumToad) > > > > Andrew, will you do my homework too?
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