Re: Select / sub select? query... help...

Jim Fitzgerald wrote:

>Hello -
>
>

Probably would be better to ask, "how do I store this data?"

Then the query writes itself. Put people in one table, put aliases in
another.

CREATE TABLE people (
person_id int
,first varchar(20)
,last varchar(20)
)

CREATE TABLE aliases (
person_id int references people (person_id)
,first varchar(20)
,last varchar(20)
)

> I'm trying to figure out how to write a particular query and need some
>assistance. I imagine this is extremely simple. I have the table defined
>below with five records. This table keeps track of peoples names. Each
>person has a unique ID number ("person_id"). The table can also keep track
>of alias names for these people. Each record has a flag ("isalias")
>indicating whether or not this record indicates a persons real name or a
>persons alias name. If it is an alias name then an additional field
>("alias") has the number indicating this persons real name record by
>person_id (ie alias field of an alias record == the person_id of the real
>name record).
>
> I want a query that will select all entries where "isalias" is true and
>will display the person_id, first, and last fields from the alias record and
>ALSO the first and last fields from the real name entry.
>
>Output would be something like this for the example data below
>
>3 - Johns - Alias - John - Smith
>4 - Marks - Alias - Mark - Twain
>
>
>Any thoughts on how this can be accomplished easily / efficiently?
>
>Thanks
>-Jim
>
>
> Table "public.people"
> Column | Type | Modifiers
>-----------+-----------------------+-----------
> person_id | integer |
> first | character varying(20) |
> last | character varying(20) |
> alias | integer |
> isalias | boolean |
>
>Containing the example data:
>
> person_id | first | last | alias | isalias
>-----------+-------+-------+-------+---------
> 1 | John | Smith | 0 | f
> 2 | Mark | Twain | 0 | f
> 3 | Johns | Alias | 1 | t
> 4 | Marks| Alias | 2 | t
> 5 | someone | else | 0| f
>
>(5 rows)
>
>
>
>
>---------------------------(end of broadcast)---------------------------
>TIP 1: if posting/reading through Usenet, please send an appropriate
> subscribe-nomail command to majordomo(at)postgresql(dot)org so that your
> message can get through to the mailing list cleanly
>
>