Video cards performance in ZCash / ZEC mining

Ошибка: Запрос select i._id, i._number, i.title, if(isnull(custom.type) or custom.type="", i.type, custom.type) as type, if(isnull(custom.date_of_announcement) or year(custom.date_of_announcement)=0, year(i.date_of_announcement), year(custom.date_of_announcement)) as year, if(isnull(custom.date_of_announcement) or year(custom.date_of_announcement)=0, i.date_of_announcement, custom.date_of_announcement) as date, i.date_of_announcement_raw as date_raw, if(isnull(custom.prof) or !custom.prof, i.prof, custom.prof) as prof, if(isnull(custom.price) or custom.price="", i.price_current, custom.price) as price, if(isnull(custom.power_consumption) or custom.power_consumption="", if(isnull(pow_value.value), i.power_consumption, pow_value.value), custom.power_consumption) as power_consumption, i.architecture, i.filename, if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result) as benchmarks from ss_cards as i left join ss_cards_custom as custom on custom.filename=i.filename and custom._disabled=0 left join ss_video_zcash as b on b.id=replace(replace(replace(replace(replace(i.title," (Desktop)",""),"NVIDIA GeForce ",""),"AMD Radeon ","")," ",""),"-","") left join ss_nicehash as n_value on n_value.type="video" and n_value.name=replace(i.title," (Desktop)","") and n_value.field="ZCash" left join ss_nicehash as pr_value on pr_value.type="video" and pr_value.name=replace(i.title," (Desktop)","") and pr_value.field="price" left join ss_nicehash as pow_value on pow_value.type="video" and pow_value.name=replace(i.title," (Desktop)","") and pow_value.field="power" left join ss_cards_custom as custom on custom.filename=i.filename left join ss_video_mining_results_custom as mining_custom on mining_custom._master_id = custom._id and mining_id=3 where i._disabled=0 and if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result)>0 and i.redirect_to=0 order by 1*if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result) desc, i._number, i.title вызвал ошибку Not unique table/alias: 'custom'

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            [file] => /var/www/web/data/www/technical.city/system/lib/db.php
            [line] => 89
            [function] => db_query
            [args] => Array
                (
                    [0] => select i._id, i._number, i.title,
	if(isnull(custom.type) or custom.type="", i.type, custom.type) as type,
	if(isnull(custom.date_of_announcement) or year(custom.date_of_announcement)=0, year(i.date_of_announcement), year(custom.date_of_announcement)) as year,
	if(isnull(custom.date_of_announcement) or year(custom.date_of_announcement)=0, i.date_of_announcement, custom.date_of_announcement) as date,
	i.date_of_announcement_raw as date_raw,
	if(isnull(custom.prof) or !custom.prof, i.prof, custom.prof) as prof,
	if(isnull(custom.price) or custom.price="", i.price_current, custom.price) as price,
	if(isnull(custom.power_consumption) or custom.power_consumption="", if(isnull(pow_value.value), i.power_consumption, pow_value.value), custom.power_consumption) as power_consumption,
	i.architecture,
	i.filename,
	if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result) as benchmarks
	from ss_cards as i
	left join 
	ss_cards_custom as custom on custom.filename=i.filename and custom._disabled=0
	left join
	ss_video_zcash as b
	on b.id=replace(replace(replace(replace(replace(i.title," (Desktop)",""),"NVIDIA GeForce ",""),"AMD Radeon ","")," ",""),"-","")
	left join
	ss_nicehash as n_value
	on n_value.type="video" and n_value.name=replace(i.title," (Desktop)","") and n_value.field="ZCash"
	left join
	ss_nicehash as pr_value
	on pr_value.type="video" and pr_value.name=replace(i.title," (Desktop)","") and pr_value.field="price"

	left join
	ss_nicehash as pow_value
	on pow_value.type="video" and pow_value.name=replace(i.title," (Desktop)","") and pow_value.field="power"
	
	left join
	ss_cards_custom as custom
	on custom.filename=i.filename	
	
	left join
	ss_video_mining_results_custom as mining_custom
	on mining_custom._master_id = custom._id and mining_id=3
	
	where i._disabled=0 and if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result)>0 and i.redirect_to=0
	order by 1*if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result) desc, i._number, i.title
                )

        )

    [1] => Array
        (
            [file] => /var/www/web/data/www/technical.city/_content/textblocks/text/68/68
            [line] => 428
            [function] => db_getAssocs
            [args] => Array
                (
                    [0] => select i._id, i._number, i.title,
	if(isnull(custom.type) or custom.type="", i.type, custom.type) as type,
	if(isnull(custom.date_of_announcement) or year(custom.date_of_announcement)=0, year(i.date_of_announcement), year(custom.date_of_announcement)) as year,
	if(isnull(custom.date_of_announcement) or year(custom.date_of_announcement)=0, i.date_of_announcement, custom.date_of_announcement) as date,
	i.date_of_announcement_raw as date_raw,
	if(isnull(custom.prof) or !custom.prof, i.prof, custom.prof) as prof,
	if(isnull(custom.price) or custom.price="", i.price_current, custom.price) as price,
	if(isnull(custom.power_consumption) or custom.power_consumption="", if(isnull(pow_value.value), i.power_consumption, pow_value.value), custom.power_consumption) as power_consumption,
	i.architecture,
	i.filename,
	if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result) as benchmarks
	from ss_cards as i
	left join 
	ss_cards_custom as custom on custom.filename=i.filename and custom._disabled=0
	left join
	ss_video_zcash as b
	on b.id=replace(replace(replace(replace(replace(i.title," (Desktop)",""),"NVIDIA GeForce ",""),"AMD Radeon ","")," ",""),"-","")
	left join
	ss_nicehash as n_value
	on n_value.type="video" and n_value.name=replace(i.title," (Desktop)","") and n_value.field="ZCash"
	left join
	ss_nicehash as pr_value
	on pr_value.type="video" and pr_value.name=replace(i.title," (Desktop)","") and pr_value.field="price"

	left join
	ss_nicehash as pow_value
	on pow_value.type="video" and pow_value.name=replace(i.title," (Desktop)","") and pow_value.field="power"
	
	left join
	ss_cards_custom as custom
	on custom.filename=i.filename	
	
	left join
	ss_video_mining_results_custom as mining_custom
	on mining_custom._master_id = custom._id and mining_id=3
	
	where i._disabled=0 and if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result)>0 and i.redirect_to=0
	order by 1*if(isnull(mining_custom.result) OR mining_custom.result=0, if(isnull(n_value.value), b.result, n_value.value), mining_custom.result) desc, i._number, i.title
                )

        )

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            [file] => /var/www/web/data/www/technical.city/_content/pages/text/34/334_1
            [line] => 4
            [args] => Array
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                    [0] => /var/www/web/data/www/technical.city/_content/textblocks/text/68/68
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            [function] => include
        )

    [3] => Array
        (
            [file] => /var/www/web/data/www/technical.city/system/handler/index.php
            [line] => 373
            [args] => Array
                (
                    [0] => /var/www/web/data/www/technical.city/_content/pages/text/34/334_1
                )

            [function] => require
        )

)