Table test_a
| genId | country | alcohol_spirits | music |
|-------|---------|-----------------|-------|
| 1 | US | 0 | 0 |
| 2 | IN | 0 | 0 |
| 3 | SE | 0 | 0 |
Table test_b
| itemId | headAlias | headDestinations | iTitle |
|--------|-----------------|------------------|----------|
| 1 | alcohol-spirits | US,SE | Bottle 1 |
| 2 | alcohol-spirits | US,SE | Bottle 2 |
| 3 | alcohol-spirits | US,SE | Bottle 3 |
| 4 | alcohol-spirits | US | Bottle 4 |
My sql
update test_a set alcohol_spirits = alcohol_spirits +
(
select
count(itemId)
from test_b
where headAlias = 'alcohol-spirits'
and headDestinations IN ('US,SE') /* 'US,SE' = user input*/
) where country IN('US,SE') ; /* 'US,SE' = user input */
I'm trying to update table test_a
with the count()
of items from test_b
for each country. It's hard to explain, but you'll see from my expected results.
For alcohol_spirits
, the US
has 4
and SE
has 3
. I'm trying to update it all at once, but what I thought would work, does not. Where am I going wrong and how to get this right?
Expected results
| genId | country | alcohol_spirits | music |
|-------|---------|-----------------|-------|
| 1 | US | 4 | 0 |
| 2 | UK | 0 | 0 |
| 3 | SE | 4 | 0 |
You can use a query for this like this
UPDATE table_a a
SET a.alcohol_spirits = a.alcohol_spirits +
(SELECT
count(table_b.itemId)
FROM table_b
WHERE headAlias = 'alcohol-spirits'
AND country IN('US,SE')
AND FIND_IN_SET(a.country, table_b.headdestinations)
)
Try this
update test_a set
alcohol_spirits=(
select alcohol_spirits+count(*) from test_b where headDestinations like '%'+country +'%')
this query will added current alcohol_spirits with every execution you shout alwase update with only count like following query
update test_a set
alcohol_spirits=(
select count(*) from test_b where headDestinations like '%'+country +'%')
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