Re: Group By? - Mailing list pgsql-general
From | Jim C. Nasby |
---|---|
Subject | Re: Group By? |
Date | |
Msg-id | 20051128221857.GD78939@pervasive.com Whole thread Raw |
In response to | Re: Group By? (Bob Pawley <rjpawley@shaw.ca>) |
List | pgsql-general |
So are you trying to get a list of all 'mon's and 'valve's for each given association? On Wed, Nov 23, 2005 at 04:31:04PM -0800, Bob Pawley wrote: > Guy > > > > Sorry about the chart. It held together when I sent it to myself. > > > > I'll try to make it clear in the way you suggest, by a truncated example. > > > > Create table control (device_id serial, type varchar, association int4) > > Create table auto_control (loop_id serial, monitor int4, valve int4) > > > > Insert into control (type, association) Note - mon and valve are types of > device that together make a loop. A loop can be from 1 to 7 devices.. > > Values ('mon', '1') - serial 1 > > Values ('valve', '2') - serial 2 > > Values ('mon', '2') - serial 3 > > Values ('valve', '1') - serial 4 > > Values ('valve', '2') - serial 5 > > > > I want to transfer the serial device_id number for mon '1' into the same > row as valve '1' in the tables auto_control. Similarily > > > > Those two rows would look like this. > > Table (loop_id serial, monitor int4, valve int4) > > Row 1 ( 1, 1, 4, ) > > Row 2 (2, 2, 3, 5) > > > > Once this is done the devices will be organized into loops and each device > in the loop will have a direct link to other parts of the database. > > > > I would like to know if this is possible with SQL, or would it be more > suited to the host language? > > > > Would it be possible in SQL to have the information transferred into the > auto_control table as the information is being entered or would the control > table need to be fully completed? > > > > Hope this is finally clear. > > > > Thanks for you help. > > > > Bob > > ----- Original Message ----- > From: "Guy Rouillier" <guyr@masergy.com> > To: "PostgreSQL General" <pgsql-general@postgresql.org> > Sent: Wednesday, November 23, 2005 2:17 PM > Subject: Re: [GENERAL] Group By? > > > Bob Pawley wrote: > >Bruno > > > >The table I previously sent came through distorted and probabley > >caused misunderstanding. > > > >The table control and auto_control are both permanent table. I want to > >reshuffle how the information is associated from one table to another > >with the link between table by way of the device_id. > > > >Following is the example which I stabilized and tested for e-mail. > > Sorry, Bob, I think the reason you haven't gotten a response is that the > information you are trying to convey below is very unclear. Perhaps you > can just provide a create table statement and a bunch of insert > statements? Then summarize again what you are trying to accomplish. > > > > >Bob > > > > Control > > > > > > > > > > > > > > > > > > > > device_id > > type > > association > > > > > > serial > > varchar > > int4 > > > > > > > > > > > > > > > > 1 > > mon > > 1 > > > > > > 2 > > valve > > 2 > > > > > > 3 > > valve > > 1 > > > > > > 4 > > mon > > 2 > > > > > > 5 > > valve > > 1 > > > > > > > > > > > > > > > > > > > > > > > > > > Auto_control > > > > > > > > > > > > > > > > > > > > loop_id > > mon > > valve_a > > valve_b > > > > serial > > int4 > > int4 > > int4 > > > > > > > > > > > > > > 1 > > 1 > > 3 > > 5 > > > > 2 > > 2 > > 4 > > > > > > > > > > > > > > > > > >----- Original Message ----- > >From: "Bruno Wolff III" <bruno@wolff.to> > >To: "Bob Pawley" <rjpawley@shaw.ca> > >Cc: "Guy Rouillier" <guyr@masergy.com>; "Postgre General" > ><pgsql-general@postgresql.org> > >Sent: Monday, November 21, 2005 10:07 PM > >Subject: Re: Group By? > > > > > >>On Mon, Nov 21, 2005 at 21:53:10 -0800, > >> Bob Pawley <rjpawley@shaw.ca> wrote: > >>>Here's what I want to do. > >>> > >>>Table control contains values (mon and valves) that are associated > >>>by numbers inserted into the associated column. > >>> > >>>I want to transfer the serial _id number of the items associated by > >>>the value '1' into the appropriate columns of the first row of the > >>>table auto_control. All items associated with the value '2' into the > >>>second row - etc. etc. > >> > >>You don't really want to do that. Tables have fixed numbers of > >>columns and what you want to do doesn't result in a fixed number of > >>columns. > >> > >>If you want to generate a report with that format, then I think there > >>is a contrib module (crosstabs?) that will do this kind of thing. You > >>could also have a report app do it for you. In the report app method, > >>you would be best to return rows ordered by association and then > >>device_ID and have the app check for when the association value > >>changes. > >> > >>> > >>>Is this best accomplished by a 'group by' command or subset??? > >>> > >>>Bob > >>> Control > >>> > >>> device_ID type association > >>> serial varchar int4 > >>> > >>> 1 mon 1 > >>> 2 valve 2 > >>> 3 valve 1 > >>> 4 mon 2 > >>> 5 valve 1 > >>> > >>> > >>> Auto_control > >>> > >>> loop_id mon valve valve > >>> serial int4 int4 int4 > >>> 1 1 3 5 > >>> 2 2 4 > >>> > >>> > >>> > >>>----- Original Message ----- > >>>From: "Guy Rouillier" <guyr@masergy.com> > >>>To: "Postgre General" <pgsql-general@postgresql.org> > >>>Sent: Monday, November 21, 2005 4:25 PM > >>>Subject: Re: [GENERAL] Group By? > >>> > >>> > >>>Converted your message to plain text as preferred on most mailing > >>>lists. > >>> > >>>Bob Pawley wrote: > >>>>I want to take the serial ID of several values in different rows in > >>>>one table and insert them into a single row of another table. > >>>> > >>>>Would the 'group by' command be the best way to do this? > >>> > >>>Could you provide an actual example? The wording of your question > >>>is a little vague and an example might help solicit an answer to the > >>>actual problem. For example, are these serial ID values all in a > >>>the same column in the source table? Or is each one in a different > >>>column? And what is the selection criteria that brings these > >>>results together? > >>> > >>>-- > >>>Guy Rouillier > >>> > >>>---------------------------(end of > >>>broadcast)--------------------------- > >>>TIP 3: Have you checked our extensive FAQ? > >>> > >>> http://www.postgresql.org/docs/faq > >>> > >>> > >>>---------------------------(end of > >>>broadcast)--------------------------- > >>>TIP 4: Have you searched our list archives? > >>> > >>> http://archives.postgresql.org > > > > -- > Guy Rouillier > > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Have you searched our list archives? > > http://archives.postgresql.org > > > ---------------------------(end of broadcast)--------------------------- > TIP 5: don't forget to increase your free space map settings > -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
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