I came across this SQL query in a web app I am pitching to replace.
I'm not going to name the guilty party, nor make any comments.
SELECT
0 as zero,
ff.f_id as f_id, f.number, f.primary_ff_id, f.template, f.`order` as f_order,
fi.id as fi_id, fi.datetime, fi.parent_fi_id, fi.`order`, fi.u_id,
ff.type, ff.id as ff_id, ff.sub_id, ff.label, ff.desc, ff.`order` as ff_order,
ff.type, ff.name,
IFNULL(t.tag, IFNULL(select_ffv.string, IFNULL(ffv.number, IFNULL(ffv.string, ffv.text)))) as value,
ffv_value.fi_id as multi_fi, ffv_value.string as multi_value,
ffp.key as ffp_key, ffp.value as ffp_value
FROM f_fieldset f
LEFT JOIN fi_item fi ON
fi.f_id = f.id
".($parent_fiid != 0 ? " AND fi.parent_fi_id = '".(strpos($parent_fiid,"-")===false ? $parent_fiid : 0)."'" : "")."
LEFT JOIN ff_field ff ON
ff.f_id = f.id
LEFT JOIN ffp_param ffp ON
ffp.ff_id = ff.id
LEFT JOIN ffv_value ffv ON
ffv.fi_id = fi.id AND
ffv.ff_id = ff.id
LEFT JOIN f_fieldset select_f ON
ff.type = 'select' AND
select_f.id = ff.sub_id
LEFT JOIN ffv_value select_ffv ON
select_ffv.fi_id = ffv.number AND
select_ffv.ff_id = select_f.primary_ff_id
LEFT JOIN f_fieldset multi_f ON
ff.type = 'multi_select' AND
multi_f.id = 1051
LEFT JOIN fi_item multi_fi ON
multi_f.id = multi_fi.f_id AND
multi_fi.parent_fi_id = fi.id
LEFT JOIN ffv_value multi_ffv ON
multi_fi.id = multi_ffv.fi_id
LEFT JOIN f_fieldset f_value ON
f_value.id = ff.sub_id
LEFT JOIN fi_item fi_value ON
fi_value.f_id = f_value.id
LEFT JOIN ffv_value ffv_value ON
ffv_value.ff_id = f_value.primary_ff_id AND
ffv_value.fi_id = fi_value.id AND
multi_ffv.number = fi_value.id
LEFT JOIN t_tags t ON
t.id = ffv.number AND
ff.f_id = 1013
WHERE
".($fid ? "f.id = '".$fid."'" : "fi.parent_fi_id = '".(strpos($parent_fiid,"-")===false ? $parent_fiid : 0)."' OR f.id BETWEEN 1000 AND 1010")."
ORDER BY
IF(
IFNULL(f.`order`,'user') = 'user',
IFNULL(fi.`order`, 2000000000 + fi.id),
IF(f.`order` = 'newest',
4294967295 - fi.datetime,
fi.datetime)
),
ff.`order`
"