Thread

({exp:query sql="SELECT count(exp_category_posts.entry_id )  AS post_count FROM exp_category_posts WHERE exp_category_posts.cat_id = {category_id}"}{post_count}{/exp:query} images in this category)

exp_weblog_titles.status='open'

SELECT
    count(exp_category_posts.entry_id) AS post_count
FROM
    exp_category_posts
NATURAL JOIN
    exp_weblog_titles
WHERE
    exp_category_posts.cat_id = {category_id}
    AND
    exp_weblog_titles.status = 'open'

({exp:query sql="SELECT
                count(exp_category_posts.entry_id) AS post_count
                FROM
                    exp_category_posts
                NATURAL JOIN
                    exp_weblog_titles
                WHERE
                    exp_category_posts.cat_id = {category_id}
                    AND
                    exp_weblog_titles.status = 'open'  = {category_id}"}{post_count}{/exp:query} images in this category)

SELECT
    count(exp_category_posts.entry_id) AS post_count
FROM
    exp_category_posts, exp_channel_titles
WHERE
    exp_category_posts.cat_id = {category_id}
    AND
    exp_category_posts.entry_id = exp_channel_titles.entry_id
    AND
    status = 'open'