Hey there, first of all please CC my email address as I'm no longer a member of this list. Recieving too much stuff already (1000+ mails a day)
Anyways I found a general SQL manual which uses oracle to show it's demos. So I tried some of the examples in there some work but don't do the expected others don't work at all. For the questions... This one I don't find really important. If you had a table a with a field tekst (text) containing "test" and a field tekst2 containing "test" according to the mysql course this statement select tekst || tekst2 total from table; should return a virtual column called total with as value testtest it returns a virtual column called total alright on it's value is 0 I also tried this with + instead of || in oracle this should give an error since it aren't numeric fields in mysql it does the same as || (or atleast so it appears) <copy from course> INPUT: SQL> SELECT * FROM FOOTBALL; OUTPUT: NAME -------------------- ABLE BRAVO CHARLIE DECON EXITOR FUBAR GOOBER 7 rows selected. INPUT: SQL> SELECT * FROM SOFTBALL; OUTPUT: NAME -------------------- ABLE BAKER CHARLIE DEAN EXITOR FALCONER GOOBER 7 rows selected. How many different people play on one team or another? INPUT/OUTPUT: SQL> SELECT NAME FROM SOFTBALL 2 UNION 3 SELECT NAME FROM FOOTBALL; NAME -------------------- ABLE BAKER BRAVO CHARLIE DEAN DECON EXITOR FALCONER FUBAR GOOBER 10 rows selected. UNION returns 10 distinct names from the two lists. How many names are on both lists (including duplicates)? INPUT/OUTPUT: SQL> SELECT NAME FROM SOFTBALL 2 UNION ALL 3 SELECT NAME FROM FOOTBALL; NAME -------------------- ABLE BAKER CHARLIE DEAN EXITOR FALCONER GOOBER ABLE BRAVO CHARLIE DECON EXITOR FUBAR GOOBER 14 rows selected. ANALYSIS: The combined list--courtesy of the UNION ALL statement--has 14 names. UNION ALL works just like UNION except it does not eliminate duplicates. Now show me a list of players who are on both teams. You can't do that with UNION--you need to learn INTERSECT. </copy> these both don't work. I searched the manual but don't see UNION at all, is it supported? I'm figuring it isn't.... SQL> SELECT * FROM FOOTBALL 2 INTERSECT 3 SELECT * FROM SOFTBALL; doesn't work either, i'm guessin intersect isn't implemented either? kind regards and have a good weekend --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
