count query

SELECT COUNT(*)
FROM (
    SELECT mcontent
    FROM (
        SELECT
            (CASE WHEN (ce.content IS NULL OR ce.content = '') THEN cp.content ELSE ce.content END) AS mcontent
        FROM copyright AS cp
        INNER JOIN uploadtree_a AS UT ON cp.pfile_fk = UT.pfile_fk
        LEFT JOIN copyright_event AS ce ON ce.copyright_fk = cp.copyright_pk
                                        AND ce.upload_fk = $5
                                        AND ce.uploadtree_fk = UT.uploadtree_pk
        WHERE cp.content != ''
            AND (UT.lft BETWEEN $1 AND $2)
            AND cp.type = $3
            AND cp.agent_fk = ANY($4::int[])
            AND (ce.is_enabled IS NULL OR ce.is_enabled = 'true')
            AND UT.upload_fk = $5
        GROUP BY mcontent

        UNION ALL

        SELECT DISTINCT textfinding AS mcontent
        FROM copyright_decision AS cd
        INNER JOIN pfile AS PF ON cd.pfile_fk = PF.pfile_pk
        INNER JOIN uploadtree_a AS UT ON PF.pfile_pk = UT.pfile_fk
        WHERE UT.lft BETWEEN $1 AND $2
            AND (cd.is_enabled IS NULL OR cd.is_enabled = 'true')
            AND UT.upload_fk = $5
    ) AS combined
) AS K;