Mysql update using values from select - mysql

Question

I have two queries. The first will return multiple rows:
SELECT parent_entry_id,child_entry_id FROM exp_playa_relationships WHERE parent_field_id = '34';
...And I would like to use the values (parent_entry_id,child_entry_id) and incorporate them into this query, replacing 'x' and 'y', and do it for each row returned by the first query.
UPDATE exp_channel_data AS t1,
(
SELECT field_id_46,field_id_47 FROM exp_channel_data WHERE entry_id = 'x') AS t2
SET t1.field_id_60 = t2.field_id_46, t1.field_id_61 = t2.field_id_47
WHERE t1.entry_id = 'y';
I think I need to use another JOIN, but I can't figure out how to implement one in my example. Any help would be much appreciated.

Answer 1

I think this is what you're after:
UPDATE exp_playa_relationships AS t0
JOIN exp_channel_data AS t1
ON t1.entry_id = t0.child_entry_id
JOIN exp_channel_data AS t2
ON t2.entry_id = t0.parent_entry_id
SET t1.field_id_60 = t2.field_id_46
, t1.field_id_61 = t2.field_id_47

Answer 2

Try this query
UPDATE exp_channel_data a1 INNER JOIN exp_playa_relationships a ON a1.entry_id = a.child_entry_id
INNER JOIN exp_channel_data b ON a.parent_entry_id = b.entri_id
SET a1.field_id_60 = b.field_id_46, ta1.field_id_61 = b.field_id_47
WHERE parent_field_id = '34'

Answer 3

Thanks all for your replies. The working syntax is:
UPDATE exp_channel_data AS t1,
(
SELECT
entry_id as ei2, child_entry_id, parent_entry_id, field_id_46 as f46,field_id_47 as f47
FROM
exp_channel_data JOIN exp_playa_relationships ON entry_id=child_entry_id AND parent_field_id = 34) AS t2
SET t1.field_id_60 = f46, t1.field_id_61 = f47
WHERE t1.entry_id=parent_entry_id;

Answer 4

Or in a more classic syntax, you need to adjust to your own foo & bar attributes, but use something like the following:
update exp_channel_data t1
set (t1.field_id_60,t1.field_id_61) = (
select t2.field_id_46 , t2.field_id_47
from exp_channel_data t2
where 1=1
and t2.entry_id = 'x'
and /* ENTER YOUR t1-t2 join condition here */
)
where 1=1
and t1.entry_id = y
;
But since you are MySQL I don't believe it supports compound subquery. As such:
update exp_channel_data t1
set t1.field_id_60 = (
select t2.field_id_46
from exp_channel_data t2
where 1=1
and t2.entry_id = 'x'
and /* ENTER YOUR t1-t2 join condition here */
) , t1.field_id_61 = (
select t3.field_id_47
from exp_channel_data t3
where 1=1
and t3.entry_id = 'x'
and /* ENTER YOUR t1-t3 join condition here */
)
where 1=1
and t1.entry_id = y
;