unique keys / foreign keys on two tables
От | Gary Stainburn |
---|---|
Тема | unique keys / foreign keys on two tables |
Дата | |
Msg-id | 201211291014.27989.gary.stainburn@ringways.co.uk обсуждение исходный текст |
Ответы |
Re: unique keys / foreign keys on two tables
|
Список | pgsql-sql |
I'm designing the schema to store a config from our switchboards. As with all PBX's the key is the dialed number which is either an extension number or a group (hunt/ring/pickup) number. I have two tables, one for extensions and one for groups, basically ext_id int4 primary key ext_desc text .... .... .... and grp_id int4 primary key grp_desc text ..... ..... ..... I now need to be able to ensure the id field is unique across both tables. Presumably I can do this with a function and a constraint for each table. Does anyone have examples of this? Next I have other tables that refer to *destinations* which will be an ID that could be either an extension or a group. Examples are 'Direct Dial In' numbers which could point to either. How would I do that? -- Gary Stainburn Group I.T. Manager Ringways Garages http://www.ringways.co.uk
В списке pgsql-sql по дате отправления: