mysql question and a really bad joke

From: Alexander Ross (alexross_at_bleen.net)
Date: 03/21/04 

Date: Sun, 21 Mar 2004 02:38:01 GMT

Lets say I have 2 tables, tbl_topics and tbl_lessons:

tbl_topics

      topicID
     INT

      parentID
     INT

      Title
     VARCHAR

tbl_lessons

      lessonID
     INT

      topicID
     INT (FK)

      Other fields

I have a query that gives me all the topics who's parentID = $whatParentID
:

"SELECT topicID FROM tbl_topics WHERE parentTopicID=$whatTopicID"

Now I want to modify this query so I get a second column called count that
contains the number of times the returned topicID is found in tbl_lessons
even if that count is 0.

Example result:

      topicID
     Count

      1000
     2

      1003
     0

      1021
     4

In this example, topics 1000,1003,and 1021 all have a parentID of 1009 (or
whatever) and 1000 has 2 lessons, 1003 has 0, and 1021 has 4.

Anyone? Anyone? Bueller? Bueller?

BAD JOKE: (read this outloud)

Have you heard about circus sex? its in tents.

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