Related link: http://dev.mysql.com/doc/mysql/en/ANSI_diff_Subqueries.html
It’s hard break the glass ceiling : to wrap your head around new programming features you didn’t have before.
MySQL 4.1 has subqueries. And I can hardly find a use for them! I’ve gotten so used to thinking of SQL without subqueries that I can’t remember what I would need them for.
I’m sure I’ll find a use someday, when frustrated that I have to write an ugly solution to something that could be done more succinctly.
But this is how I feel with learning new programming languages, for example, where I find a language has Feature X, which I’ve never worked with before. My head is used to the limitation.
I guess that’s why it’s good to learn new languages. (Read Paul Graham’s essays on Lisp here and here - and the Pragmatic Programmers Language of the Year project.)
it's all what you're used to
Myself, I've used subqueries so often I find it hard to think of doing without.
Maybe I'm spoiled of always having had major RDBMS systems to play with (DB/2, Oracle, Sybase, Tandem nonstop/SQL, Interbase).
Oracle
I'm in the same boat with Oracle. I've used DB2 and ADABAS and MySQL. CD Baby has grown up enough to use a more sophisticated DBMS. Why not look into Oracle? I am a PeopleSoft and ACUATE programmer. We have so many effective dated rows. I use subqueries to get at the most recent record (but not FUTURE records) a LOT
For example....
AND DST.EFFDT = (
SELECT MAX(A_ED.EFFDT)
FROM PS_DST_CODE_TBL A_ED
WHERE DST.SETID = A_ED.SETID
AND DST.DST_ID = A_ED.DST_ID
AND A_ED.EFFDT <= SYSDATE)