Select Query by Pair of fields using an in clause

Question

I have a table called players as follows:

First_Id    Second_Id     Name
1           1             Durant
2           1             Kobe
1           2             Lebron
2           2             Dwight
1           3             Dirk

I wish to write a select statement on this table to retrieve all rows whose first ids and second ids match a bunch of specified first and second ids.

So for example, I wish to select all rows whose first and second ids are as follows: (1,1), (1,2) and (1,3). This would retreive the following 3 rows:

First_Id    Second_Id    Name
1           1            Durant
1           2            Lebron
1           3            Dirk

Is it possible to write a select query in a manner such as:

SELECT * 
FROM PLAYERS
WHERE (First_Id, Second_Id) IN ((1,1), (1,2) and (1,3))?

If there is a way to write the SQL similar to the above I would like to know. Is there a way to specify values for an IN clause that represents multiple rows as illustrated.

I'm using DB2.

Lilongwe

Answer 1

This works on my DB2 (version 9.7 on Linux/Unix/Windows) by using this syntax:

SELECT *
FROM PLAYERS
WHERE (First_Id, Second_Id) IN (VALUES (1,1), (1,2), (1,3))

This syntax won't work on DB2 on the Mainframe (at least in version 9.1) because you can't substitute a sub-select with a VALUES expression. This syntax will work:

SELECT *
FROM PLAYERS
WHERE (First_Id, Second_Id) IN (SELECT 1, 1 FROM SYSIBM.SYSDUMMY1 UNION ALL
                                SELECT 1, 2 FROM SYSIBM.SYSDUMMY1 UNION ALL
                                SELECT 1, 3 FROM SYSIBM.SYSDUMMY1)

Joycelynjoye

This is not standard SQL but it provides a database-specific solution. – Caucasus

@GordonLinoff I agree, but he did say he was using DB2. :) – Joycelynjoye

The first syntax (WHERE (f, s) IN (VALUES (1,1), (1,2))) also works in PostgreSQL, and in docs it said that it is kind of standard SQL: postgresql.org/docs/current/static/sql-values.html – Vitric

Answer 2

Here's a very similar solution in postgresql:

SELECT tmp_table.val1, tmp_table.val2
FROM tmp_table
WHERE (tmp_table.val1, tmp_table.val2) not in (select tmp_table2.val1, tmp_table2.val2 from tmp_table2);

Caseinogen

NOTE: This isn't exactly what was asked for, I used the previous comments to solve my specific problem of inserting two values, val1, val2 from a temp table into an actual table, while this actual table had a unique key on (val1, val2). I had to find a way to remove those key pair in my tmp_table prior to inserting. This is the select part of the clause on my insert. – Caseinogen

Answer 3

With compound primary keys, I would concatenate the two ids and match compound strings.

select id1 + id2 as FullKey, *
from players
where FullKey in ('11','12','13')

(If ids are not strings, simply cast them as such.)

Esprit

Although concatenating the key columns is a useful approach, it's safer to include a delimiter character between the columns. Although the ORDER BY clause can reference a column alias such as FullKey in this example, DB2 only allows table aliases but not column aliases in the WHERE clause. – Colombia

I see. Did not realise DB2 had such a constraint on column aliases. Still, using the compound id1 + id2 (or id1 + delim + id2, which, you're right, is a better idea) in the WHERE should do the trick. – Esprit

You need to add a delimiter which you have to make sure not being in the result. There will always be the possibility of duplicates like ('ab', 'cd') and ('abc', 'd') both concatenating to abcd – Ballroom

Answer 4

This syntax works in MySQL:

SELECT *
FROM PLAYERS
WHERE (First_Id, Second_Id) IN ((1,1), (1,2), (1,3))

Navarra

Answer 5

SELECT * FROM <your table> where (<field1>, <field2>, ...) in (SELECT <field1>, <field2>, ... FROM <your table> where <your condition>)

This worked wonder for me.

Thisbee

Thank you! It worked for me in TimescaleDB 2.0 and EXPLAIN ANALYZE shows some performance improvement. – Kahle

Answer 6

This type of query works in DB2.

SELECT * FROM A
WHERE (C1, C2) IN (SELECT B1, B2 FROM B WHERE B3=1);

Bouncy

Answer 7

If data is needed in below order:

First_Id	Second_Id	Name
1	1	Durant
1	2	Lebron
1	3	Dirk
2	1	Kobe
2	2	Dwight

then simple and easy way would be:

select * from players order by First_id, second_id;

"where" clause can be used if any condition is needed on any of the column.

Koller