Hi
>A group_id cannot be both 1 AND 3, but it can be 1 OR 3.
>Try OR
Yes. I know that group_id can't be both 1 and 3 at the same time. This is
exactly
my problem. How to find a record that belongs to both groups 1 AND 3?
If I use OR here, I get also records that only belong to group 1 or only
belong to group 3. But I don't want these records.
For example:
I have three records A, B and C. A belongs to groups 1 and 2, B belongs to
group
1 and C belongs to group 2. Now I wan't to find a record that belongs to
groups
1 AND 2. (So I want that the result for my query is only group A) How can I
do that?
Not with OR I think.
Any ideas? Or do I just have to take everything out from DB and then
manually
loop through all records in my client code?
Sincerely,
Jouni Hartikainen
kalle_kukkanen@stripped
>Jouni Hartikainen wrote:
>
>>
>>Hi.
>>
>>> > how about:
>>> >
>>> > select record.*
>>> > from link
>>> > where group_id='x'
>>> > left join record on record.archive_id=link.archive_id
>>> > ?
>>
>>
>>The problem with this query is that with simple left join, I can search
>>only by a single group.
>>If I set x to 3 here, I get all records that belong to group 3. But what
>>about if I want to have all records that belong to groups 1 AND 3? If I
>>add condition "WHERE group_id='1' AND group_id='3'", I get no results at
>>all, since left join doesn't produce such rows that have multiple group_id
>>columns.
>>
>>
>>Sincerely,
>>
>>Jouni Hartikainen
>>kalle_kukkanen@stripped
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