PHP & MySQL recordset question

Question

Hello all,
I've been searching for a while, and I can't seem to find an
answer, so sorry if this has been asked a lot.
I've got 5 tables that have similar information (id,
firstname, lastname, topic, thread, and date).
What I'm trying to do is have one search box where the user
types in a keyword. Then it searches all 5 tables in both the topic
and thread collumns. Then it displays the results from all 5 tables
and orders them by date.
I'm using dreamweaver 8, PHP, and MySQL.
I've tried to use this format:
SELECT column1 column 2
FROM table1
WHERE thread OR topic LIKE %variable%
UNION
SELECT column 1 column2
FROM table 2
WHERE thread OR topic LIKE %variable%
ORDER by date DESC
but keep getting error messages.
Is this possible? If so, can anyone help me figure out how to
do this, or where I can find a good tutorial?
Thanks.

Answer 1

Thanks for your reply.
Sorry, here is the entire SQL statement:
SELECT eventforum.FirstName, eventforum.LastName,
eventforum.topic, eventforum.Thread, eventforum.`Date`
FROM eventforum
WHERE Thread or topic LIKE %colname%
UNION
SELECT fundforum.FirstName, fundforum.LastName,
fundforum.topic, fundforum.Thread, fundforum.`Date`
FROM fundforum
WHERE Thread OR topic LIKE %colname%
UNION
SELECT generalforum.FirstName, generalforum.LastName,
generalforum.topic, generalforum.Thread, generalforum.`Date`
FROM generalforum
WHERE Thread OR topic LIKE %colname%
UNION
SELECT persupport.FirstName, persupport.LastName,
persupport.topic, persupport.Thread, persupport.`Date`
FROM persupport
WHERE Thread OR topic LIKE %colname%
UNION
SELECT prosupport.FirstName, prosupport.LastName,
prosupport.topic, prosupport.Thread, prosupport.`Date`
FROM prosupport
WHERE Thread OR topic LIKE %colname%
UNION
SELECT soldier.FirstName, soldier.LastName, soldier.topic,
soldier.Thread, soldier.`Date`
FROM soldier
WHERE Thread OR topic LIKE %colname%
ORDER BY 'Date' DESC
the variable colname is defined as:
Name: colname
Type: Text
Default Value: -1
Runtime value: $_POST['searchbox']
here is the error message that I get with this setup:
Missing type for variable:colname
If I remove the variable and the WHERE statements, I get this
error message:
MySQL Error #: 1271
Illegal mix of collations for operation 'UNION'
If I remove the variable, the WHERE staements, and the ORDER
BY statement, I get the following error message:
MySQL Error #: 1271
Illegal mix of collations for operation 'UNION'