Another unknown column name error in ON clause

Question

Query:

SELECT  c.title AS title
            , c.introtext AS body
            , c.state AS state
            , c.created AS created
            , c.created_by AS         


        

Answer 1

You preform the join between jos_categories and jos_categories AS jc:

jos_content AS c, jos_categories
INNER JOIN jos_categories AS jc
ON c.sectionid = jc.section

but c is jos_content...

Answer 2

change your FROM clause to:

FROM   jos_content AS c
INNER JOIN jos_categories AS jc 
ON c.sectionid = jc.section 
WHERE c.sectionid = 7