sqlfriends (11/9/2011)
Thanks, so above statement, for inner join it doesn't need to join on a matched column?
That's right, the SQL language doesn't force people to write joins that make sense.
I just feel it's kind of hard for me to understand this cross join.
I'm not surprised. Writing joins naturally, with proper join conditions in the ON clause and other non-join filters in the WHERE clause makes life easier for everyone. If it were me, I would rewrite these using explicit CROSS JOIN syntax.
Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi