Re: Join question

have you tried a right Join?Daniel Hernndez.San Diego, CA."The more you learn, the more you earn".Fax: (808) 442-0427-----Original Message-----From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]Date: 08/15/2008 09:48 AMTo: pgsql-sql(at)postgresql(dot)orgSubject: Re: [SQL] Join question I have 2 tables, both have a user column. I am currently using a left join from table a to table b because I need to show all users from table a even those not having an entry in table b. The problem is I also have to include items from table b with that have a null user. There are some other criteria as well that are simple where clause filters. So as an example:   Table a: Org|user A    | emp1 B    | emp1 B    | emp2 B    | emp3 C    | emp2   Table b: Org|user|color A   |emp1|red A   |emp1|blue A   |null|pink A   |null|orange B   |emp1|red B   |emp3|red B   |null|silver C   |emp2|avacado   If I:   select org, user, count(total) from a left join b on (a.org = b.org and a.user = b.user) where a.org = ‘A’ group by a.org, a.user order by a.org, a.user   I get:   Org|user|count A    |emp1|2 A    |emp2|0 A    |emp3|0   But what I need is:   A    |emp1|2 A    |emp2|0 A    |emp3|0 A    |null|2   Thanks, Edward W. Rouse

I don't understand your count(total) expression...
It doesnt work, because apparently you dont have any "total" column...
Apparently, you meant count(color)

The problem is that you are grouping by a.org,a.user and on table "a" u actually dont have any "null" users...

Well, if it is to include "null" users, a quick and dirty solution I can think of would be to add a "dummy" null user to every diferent org on table a and then
substitute your LEFT OUTER JOIN condition by this one :

from a left join b

on (a.org = b.org and (a.user = b.user OR (a.user is null and b.user is null )))

Now, I don' know if "null" users on table "a" will violate any constraints you may have (e.g. NOT NULL) ...

I know This is not a very elegant solution, but seems to give the results you need....

Best,
Oliveiros
----- Original Message -----
From: Daniel Hernandez
To: pgsql-sql(at)postgresql(dot)org ; erouse(at)comsquared(dot)com
Sent: Monday, August 18, 2008 5:30 PM
Subject: Re: [SQL] Join question

have you tried a right Join?

Daniel Hernndez.
San Diego, CA.
"The more you learn, the more you earn".
Fax: (808) 442-0427

-----Original Message-----
From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
Date: 08/15/2008 09:48 AM
To: pgsql-sql(at)postgresql(dot)org
Subject: Re: [SQL] Join question

I have 2 tables, both have a user column. I am currently using a left join from table a to table b because I need to show all users from table a even those not having an entry in table b. The problem is I also have to include items from table b with that have a null user. There are some other criteria as well that are simple where clause filters. So as an example:

Table a:

Org|user

A | emp1

B | emp1

B | emp2

B | emp3

C | emp2

Table b:

Org|user|color

A |emp1|red

A |emp1|blue

A |null|pink

A |null|orange

B |emp1|red

B |emp3|red

B |null|silver

C |emp2|avacado

If I:

select org, user, count(total)

from a left join b

on (a.org = b.org and a.user = b.user)

where a.org = ‘A’

group by a.org, a.user

order by a.org, a.user

I get:

Org|user|count

A |emp1|2

A |emp2|0

A |emp3|0

But what I need is:

A |emp1|2

A |emp2|0

A |emp3|0

A |null|2

Thanks,

Edward W. Rouse

I have tried left, right outer and inner.

Edward W. Rouse

From: Daniel Hernandez [mailto:breydan(at)excite(dot)com]
Sent: Monday, August 18, 2008 12:30 PM
To: pgsql-sql(at)postgresql(dot)org; erouse(at)comsquared(dot)com
Subject: Re: [SQL] Join question

have you tried a right Join?

Daniel Hernndez.
San Diego, CA.
"The more you learn, the more you earn".
Fax: (808) 442-0427

-----Original Message-----
From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
Date: 08/15/2008 09:48 AM
To: pgsql-sql(at)postgresql(dot)org
Subject: Re: [SQL] Join question

I have 2 tables, both have a user column. I am currently using a left join from table a to table b because I need to show all users from table a even those not having an entry in table b. The problem is I also have to include items from table b with that have a null user. There are some other criteria as well that are simple where clause filters. So as an example:

Table a:

Org|user

A | emp1

B | emp1

B | emp2

B | emp3

C | emp2

Table b:

Org|user|color

A |emp1|red

A |emp1|blue

A |null|pink

A |null|orange

B |emp1|red

B |emp3|red

B |null|silver

C |emp2|avacado

If I:

select org, user, count(total)

from a left join b

on (a.org = b.org and a.user = b.user)

where a.org = ‘A’

group by a.org, a.user

order by a.org, a.user

I get:

Org|user|count

A |emp1|2

A |emp2|0

A |emp3|0

But what I need is:

A |emp1|2

A |emp2|0

A |emp3|0

A |null|2

Thanks,

Edward W. Rouse

I thought of that, but it does violate table constraints.

Edward W. Rouse

From: Oliveiros Cristina [mailto:oliveiros(dot)cristina(at)marktest(dot)pt]
Sent: Monday, August 18, 2008 2:00 PM
To: pgsql-sql(at)postgresql(dot)org; erouse(at)comsquared(dot)com
Subject: Re: [SQL] Join question

I don't understand your count(total) expression...

It doesnt work, because apparently you dont have any "total" column...

Apparently, you meant count(color)

The problem is that you are grouping by a.org,a.user and on table "a" u actually dont have any "null" users...

Well, if it is to include "null" users, a quick and dirty solution I can think of would be to add a "dummy" null user to every diferent org on table a and then

substitute your LEFT OUTER JOIN condition by this one :

from a left join b

on (a.org = b.org and (a.user = b.user OR (a.user is null and b.user is null )))

Now, I don' know if "null" users on table "a" will violate any constraints you may have (e.g. NOT NULL) ...

I know This is not a very elegant solution, but seems to give the results you need....

Best,

Oliveiros

----- Original Message -----

From: Daniel Hernandez <mailto:breydan(at)excite(dot)com>

To: pgsql-sql(at)postgresql(dot)org ; erouse(at)comsquared(dot)com

Sent: Monday, August 18, 2008 5:30 PM

Subject: Re: [SQL] Join question

have you tried a right Join?

Daniel Hernndez.
San Diego, CA.
"The more you learn, the more you earn".
Fax: (808) 442-0427

-----Original Message-----
From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
Date: 08/15/2008 09:48 AM
To: pgsql-sql(at)postgresql(dot)org
Subject: Re: [SQL] Join question

I have 2 tables, both have a user column. I am currently using a left join from table a to table b because I need to show all users from table a even those not having an entry in table b. The problem is I also have to include items from table b with that have a null user. There are some other criteria as well that are simple where clause filters. So as an example:

Table a:

Org|user

A | emp1

B | emp1

B | emp2

B | emp3

C | emp2

Table b:

Org|user|color

A |emp1|red

A |emp1|blue

A |null|pink

A |null|orange

B |emp1|red

B |emp3|red

B |null|silver

C |emp2|avacado

If I:

select org, user, count(total)

from a left join b

on (a.org = b.org and a.user = b.user)

where a.org = ‘A’

group by a.org, a.user

order by a.org, a.user

I get:

Org|user|count

A |emp1|2

A |emp2|0

A |emp3|0

But what I need is:

A |emp1|2

A |emp2|0

A |emp3|0

A |null|2

Thanks,

Edward W. Rouse

Already tried making two queries and then outputting the UNION of the results?

The second one could be something like this...

SELECT org,null,COUNT(color)
FROM b
WHERE user IS NULL
AND org = 'a'
GROUP BY org

Best,
Oliveiros
----- Original Message -----
From: Edward W. Rouse
To: pgsql-sql(at)postgresql(dot)org
Sent: Tuesday, August 19, 2008 2:36 PM
Subject: Re: [SQL] Join question

I thought of that, but it does violate table constraints.

Edward W. Rouse

From: Oliveiros Cristina [mailto:oliveiros(dot)cristina(at)marktest(dot)pt]
Sent: Monday, August 18, 2008 2:00 PM
To: pgsql-sql(at)postgresql(dot)org; erouse(at)comsquared(dot)com
Subject: Re: [SQL] Join question

I don't understand your count(total) expression...

It doesnt work, because apparently you dont have any "total" column...

Apparently, you meant count(color)

The problem is that you are grouping by a.org,a.user and on table "a" u actually dont have any "null" users...

Well, if it is to include "null" users, a quick and dirty solution I can think of would be to add a "dummy" null user to every diferent org on table a and then

substitute your LEFT OUTER JOIN condition by this one :

from a left join b

on (a.org = b.org and (a.user = b.user OR (a.user is null and b.user is null )))

Now, I don' know if "null" users on table "a" will violate any constraints you may have (e.g. NOT NULL) ...

I know This is not a very elegant solution, but seems to give the results you need....

Best,

Oliveiros

----- Original Message -----

From: Daniel Hernandez

To: pgsql-sql(at)postgresql(dot)org ; erouse(at)comsquared(dot)com

Sent: Monday, August 18, 2008 5:30 PM

Subject: Re: [SQL] Join question

have you tried a right Join?

Daniel Hernndez.
San Diego, CA.
"The more you learn, the more you earn".
Fax: (808) 442-0427

-----Original Message-----
From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
Date: 08/15/2008 09:48 AM
To: pgsql-sql(at)postgresql(dot)org
Subject: Re: [SQL] Join question

I have 2 tables, both have a user column. I am currently using a left join from table a to table b because I need to show all users from table a even those not having an entry in table b. The problem is I also have to include items from table b with that have a null user. There are some other criteria as well that are simple where clause filters. So as an example:

Table a:

Org|user

A | emp1

B | emp1

B | emp2

B | emp3

C | emp2

Table b:

Org|user|color

A |emp1|red

A |emp1|blue

A |null|pink

A |null|orange

B |emp1|red

B |emp3|red

B |null|silver

C |emp2|avacado

If I:

select org, user, count(total)

from a left join b

on (a.org = b.org and a.user = b.user)

where a.org = ‘A’

group by a.org, a.user

order by a.org, a.user

I get:

Org|user|count

A |emp1|2

A |emp2|0

A |emp3|0

But what I need is:

A |emp1|2

A |emp2|0

A |emp3|0

A |null|2

Thanks,

Edward W. Rouse

--- On Tue, 8/19/08, Edward W. Rouse <erouse(at)comsquared(dot)com> wrote:

> From: Edward W. Rouse <erouse(at)comsquared(dot)com>
> Subject: Re: [SQL] Join question
> To: "'Daniel Hernandez'" <breydan(at)excite(dot)com>, pgsql-sql(at)postgresql(dot)org
> Date: Tuesday, August 19, 2008, 1:35 PM
> I have tried left, right outer and inner.
>
>
>
> Edward W. Rouse
>
>
>
> From: Daniel Hernandez [mailto:breydan(at)excite(dot)com]
> Sent: Monday, August 18, 2008 12:30 PM
> To: pgsql-sql(at)postgresql(dot)org; erouse(at)comsquared(dot)com
> Subject: Re: [SQL] Join question
>
>
>
> have you tried a right Join?
>
>
> Daniel Hernndez.
> San Diego, CA.
> "The more you learn, the more you earn".
> Fax: (808) 442-0427
>
>
> -----Original Message-----
> From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
> Date: 08/15/2008 09:48 AM
> To: pgsql-sql(at)postgresql(dot)org
> Subject: Re: [SQL] Join question
>
> I have 2 tables, both have a user column. I am currently
> using a left join from table a to table b because I need to
> show all users from table a even those not having an entry
> in table b. The problem is I also have to include items from
> table b with that have a null user. There are some other
> criteria as well that are simple where clause filters. So as
> an example:
>
>
>
> Table a:
>
> Org|user
>
> A | emp1
>
> B | emp1
>
> B | emp2
>
> B | emp3
>
> C | emp2
>
>
>
> Table b:
>
> Org|user|color
>
> A |emp1|red
>
> A |emp1|blue
>
> A |null|pink
>
> A |null|orange
>
> B |emp1|red
>
> B |emp3|red
>
> B |null|silver
>
> C |emp2|avacado
>
>
>
> If I:
>
>
>
> select org, user, count(total)
>
> from a left join b
>
> on (a.org = b.org and a.user = b.user)
>
> where a.org = ‘A’
>
> group by a.org, a.user
>
> order by a.org, a.user
>
>
>
> I get:
>
>
>
> Org|user|count
>
> A |emp1|2
>
> A |emp2|0
>
> A |emp3|0
>
>
>
> But what I need is:
>
>
>
> A |emp1|2
>
> A |emp2|0
>
> A |emp3|0
>
> A |null|2
>
>
>
> Thanks,
>
> Edward W. Rouse

also like this...

select id1,dato1, count(id2) from
(
select pr1.id as id1,pr1.dato as dato1,pr2.oid as id2,pr2.dato from pr1 right outer join pr2 on (pr1.id = pr2.oid)
) a group by id1,dato1

I was trying to do something like this, but couldn't get it to work. I am trying to follow the example you provided, but don't understand how id and oid relate to the example tables and which table is pr1 and pr2. Also my data has to match 2 constraints, not 1 (though I'm guessing that I could just add the other without changing anything else). And you have pr2.dato in the inner select but not the outer one. Is there a reason for that.

As of now I am thinking I will have to break this up into more than one statement.

Edward W. Rouse

-----Original Message-----
From: pgsql-sql-owner(at)postgresql(dot)org [mailto:pgsql-sql-owner(at)postgresql(dot)org] On Behalf Of Lennin Caro
Sent: Tuesday, August 19, 2008 11:59 AM
To: 'Daniel Hernandez'; pgsql-sql(at)postgresql(dot)org; Edward W. Rouse
Subject: Re: [SQL] Join question

--- On Tue, 8/19/08, Edward W. Rouse <erouse(at)comsquared(dot)com> wrote:

> From: Edward W. Rouse <erouse(at)comsquared(dot)com>
> Subject: Re: [SQL] Join question
> To: "'Daniel Hernandez'" <breydan(at)excite(dot)com>, pgsql-sql(at)postgresql(dot)org
> Date: Tuesday, August 19, 2008, 1:35 PM
> I have tried left, right outer and inner.
>
>
>
> Edward W. Rouse
>
>
>
> From: Daniel Hernandez [mailto:breydan(at)excite(dot)com]
> Sent: Monday, August 18, 2008 12:30 PM
> To: pgsql-sql(at)postgresql(dot)org; erouse(at)comsquared(dot)com
> Subject: Re: [SQL] Join question
>
>
>
> have you tried a right Join?
>
>
> Daniel Hernndez.
> San Diego, CA.
> "The more you learn, the more you earn".
> Fax: (808) 442-0427
>
>
> -----Original Message-----
> From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
> Date: 08/15/2008 09:48 AM
> To: pgsql-sql(at)postgresql(dot)org
> Subject: Re: [SQL] Join question
>
> I have 2 tables, both have a user column. I am currently
> using a left join from table a to table b because I need to
> show all users from table a even those not having an entry
> in table b. The problem is I also have to include items from
> table b with that have a null user. There are some other
> criteria as well that are simple where clause filters. So as
> an example:
>
>
>
> Table a:
>
> Org|user
>
> A | emp1
>
> B | emp1
>
> B | emp2
>
> B | emp3
>
> C | emp2
>
>
>
> Table b:
>
> Org|user|color
>
> A |emp1|red
>
> A |emp1|blue
>
> A |null|pink
>
> A |null|orange
>
> B |emp1|red
>
> B |emp3|red
>
> B |null|silver
>
> C |emp2|avacado
>
>
>
> If I:
>
>
>
> select org, user, count(total)
>
> from a left join b
>
> on (a.org = b.org and a.user = b.user)
>
> where a.org = ‘A’
>
> group by a.org, a.user
>
> order by a.org, a.user
>
>
>
> I get:
>
>
>
> Org|user|count
>
> A |emp1|2
>
> A |emp2|0
>
> A |emp3|0
>
>
>
> But what I need is:
>
>
>
> A |emp1|2
>
> A |emp2|0
>
> A |emp3|0
>
> A |null|2
>
>
>
> Thanks,
>
> Edward W. Rouse

also like this...

select id1,dato1, count(id2) from
(
select pr1.id as id1,pr1.dato as dato1,pr2.oid as id2,pr2.dato from pr1 right outer join pr2 on (pr1.id = pr2.oid)
) a group by id1,dato1

Finally got it to work. I used 2 separate selects and a union. So one of the selects was like my original left outer joined select and then I unioned it with one that got the missed nulls from the other table.

Thanks for all the advice.

Edward W. Rouse

-----Original Message-----
From: pgsql-sql-owner(at)postgresql(dot)org [mailto:pgsql-sql-owner(at)postgresql(dot)org] On Behalf Of Edward W. Rouse
Sent: Tuesday, August 19, 2008 2:04 PM
To: pgsql-sql(at)postgresql(dot)org
Subject: Re: [SQL] Join question

I was trying to do something like this, but couldn't get it to work. I am trying to follow the example you provided, but don't understand how id and oid relate to the example tables and which table is pr1 and pr2. Also my data has to match 2 constraints, not 1 (though I'm guessing that I could just add the other without changing anything else). And you have pr2.dato in the inner select but not the outer one. Is there a reason for that.

As of now I am thinking I will have to break this up into more than one statement.

Edward W. Rouse

-----Original Message-----
From: pgsql-sql-owner(at)postgresql(dot)org [mailto:pgsql-sql-owner(at)postgresql(dot)org] On Behalf Of Lennin Caro
Sent: Tuesday, August 19, 2008 11:59 AM
To: 'Daniel Hernandez'; pgsql-sql(at)postgresql(dot)org; Edward W. Rouse
Subject: Re: [SQL] Join question

--- On Tue, 8/19/08, Edward W. Rouse <erouse(at)comsquared(dot)com> wrote:

> From: Edward W. Rouse <erouse(at)comsquared(dot)com>
> Subject: Re: [SQL] Join question
> To: "'Daniel Hernandez'" <breydan(at)excite(dot)com>, pgsql-sql(at)postgresql(dot)org
> Date: Tuesday, August 19, 2008, 1:35 PM
> I have tried left, right outer and inner.
>
>
>
> Edward W. Rouse
>
>
>
> From: Daniel Hernandez [mailto:breydan(at)excite(dot)com]
> Sent: Monday, August 18, 2008 12:30 PM
> To: pgsql-sql(at)postgresql(dot)org; erouse(at)comsquared(dot)com
> Subject: Re: [SQL] Join question
>
>
>
> have you tried a right Join?
>
>
> Daniel Hernndez.
> San Diego, CA.
> "The more you learn, the more you earn".
> Fax: (808) 442-0427
>
>
> -----Original Message-----
> From: "Edward W. Rouse" [erouse(at)comsquared(dot)com]
> Date: 08/15/2008 09:48 AM
> To: pgsql-sql(at)postgresql(dot)org
> Subject: Re: [SQL] Join question
>
> I have 2 tables, both have a user column. I am currently
> using a left join from table a to table b because I need to
> show all users from table a even those not having an entry
> in table b. The problem is I also have to include items from
> table b with that have a null user. There are some other
> criteria as well that are simple where clause filters. So as
> an example:
>
>
>
> Table a:
>
> Org|user
>
> A | emp1
>
> B | emp1
>
> B | emp2
>
> B | emp3
>
> C | emp2
>
>
>
> Table b:
>
> Org|user|color
>
> A |emp1|red
>
> A |emp1|blue
>
> A |null|pink
>
> A |null|orange
>
> B |emp1|red
>
> B |emp3|red
>
> B |null|silver
>
> C |emp2|avacado
>
>
>
> If I:
>
>
>
> select org, user, count(total)
>
> from a left join b
>
> on (a.org = b.org and a.user = b.user)
>
> where a.org = ‘A’
>
> group by a.org, a.user
>
> order by a.org, a.user
>
>
>
> I get:
>
>
>
> Org|user|count
>
> A |emp1|2
>
> A |emp2|0
>
> A |emp3|0
>
>
>
> But what I need is:
>
>
>
> A |emp1|2
>
> A |emp2|0
>
> A |emp3|0
>
> A |null|2
>
>
>
> Thanks,
>
> Edward W. Rouse

also like this...

select id1,dato1, count(id2) from
(
select pr1.id as id1,pr1.dato as dato1,pr2.oid as id2,pr2.dato from pr1 right outer join pr2 on (pr1.id = pr2.oid)
) a group by id1,dato1

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