如何使用UNION在mysql中选择两个表？ [重复]

https://drive.google.com/file/d/0ByVhijs7bMwjUUZQRHpXUHFvODg/edit?usp=sharing

this s my code

i cant select the product_name and price form two tables"herbs" and "fruits" by using UNION i am a very beginner of php and mysql please help me

$results = $mysqli->query("SELECT * FROM fruits UNION SELECT * FROM herbs WHERE product_code='$product_code' LIMIT 1");
$obj = $results->fetch_object();

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I would advise you to read this tutorial first. The where keyword should be used for each table. Like this:

$results = $mysqli->query("SELECT * FROM fruits WHERE product_code='$product_code' UNION SELECT * FROM herbs WHERE product_code='$product_code' LIMIT 1");
$obj = $results->fetch_object();

try this

$results = $mysqli->query(" 
                          SELECT * FROM fruits WHERE t.product_code='$product_code'
                           UNION 
                           SELECT * FROM herbs WHERE t.product_code='$product_code' 
                           LIMIT 1");
$obj = $results->fetch_object();