Re: please give me select sqls examples to distinct these!

["David G. Johnston" <david.g.johnston@xxxxxxxxx>]

On Tue, Oct 25, 2022 at 7:06 AM Rob Sargent <robjsargent@xxxxxxxxx> wrote:

On Oct 25, 2022, at 7:55 AM, jacktby@xxxxxxxxx wrote:



typedef enum SetOperation

{

    SETOP_NONE = 0,

    SETOP_UNION,

    SETOP_INTERSECT,

    SETOP_EXCEPT

} SetOperation;

---

jacktby@xxxxxxxxx

Please use just text. 

What ‘dialect’ are using? In Postgres

0: select * from table

1: select * from table union select * from table is same shape

2: select * from table join table b on Id = idb 

3: select * from table except select * from tableb

#2 is probably conceptually correct but in this context should be written as:

SELECT *

FROM table

INTERSECT

SELECT *

FROM table

Distinct is a default modifier, one can specify ALL if that isn't desired.

This is trivially answered by the documentation as well:

https://www.postgresql.org/docs/current/queries-union.html

David J.