Select Query by Pair of fields using an in clause

问题

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.

回答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)

回答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);

回答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.)

回答4:

This type of query works in DB2.

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

回答5:

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

This worked wonder for me.

来源：https://stackoverflow.com/questions/10725901/select-query-by-pair-of-fields-using-an-in-clause

标签

sql

database

db2

in-clause