Question

Consider the following tables :

account => ID, Login, Pass, Email, Level, IDNum, Name
records => RID, Status, IDNum, Reason, Type, Amount, Date, SubmitterID

Now I join the tables with the following query:

SELECT account.Name FROM account, records WHERE records.IDNum = account.IDNum

In the query above the Name field would be joined based on matching IDNum, however if I want to get the Name field WHERE account.ID = records.ID and also WHERE records.IDNum = account.IDNum simultaneously, would that be possible?

Question in short, joining the 2 queries below into one :

SELECT account.Name FROM account, records WHERE records.IDNum = account.IDNum
SELECT account.Name FROM account, records WHERE records.SubmitterID = account.ID

I’m probably not clear enough, please check the example data below :

So obviously the Name field of the first query would return John, and return Chris for the second query. I want to display both names in one query.

Answer 1

You are actually joinging EVERY rows and then filter out to retains only the one you want. You should instead filter them out right with the join:

select account.Name
FROM account
    INNER JOIN records ON (records.IDNum = account.IDNum AND records.SubmitterID = account.ID)

EDIT: by OP question edit

Seems you need and OR instead of AND in the above JOIN. Thus:

select account.Name
FROM account
    INNER JOIN records ON (records.IDNum = account.IDNum OR records.SubmitterID = account.ID)

EDIT 2: follow-up to comment by OP

create table account (id int, IDNum int, Name char(5));
insert into account values (1, 12345, 'John'), (2, NULL, 'Chris');
create table records (RID int, IDNum int, SubmitterID int);
insert into records values (1, 12345, 2);
select account.Name
FROM account
    INNER JOIN records ON (records.IDNum = account.IDNum OR records.SubmitterID = account.ID);

yields (with MySQL 5.1.46):

+-------+
| Name  |
+-------+
| John  |
| Chris |
+-------+

EDIT 3: By OP second comment:

Something like this?

select account.Name as byIDNum, NULL bySubmitterID
from account
    inner join records USING (IDNum)
union
select NULL, account.Name
from account
    inner join records ON (records.SubmitterID = account.ID);