sql - Help with SQLITE query -



sql - Help with SQLITE query -

i have 3 tables task , tasktag , tag below..

create table task (task_id text primary key, subject text); create table tasktag (task_tag_id text primary key, task_id text, tag_id text); create table tag (tag_id text primary key, tag text);

i want find record in task there 2 matching tags: tag1, tag2

how sql look, have tried can't work using and, can using or..

select * task bring together tasktag on task.task_id = tasktag.task_id bring together tag on tasktag.tag_id = tag.tag_id tag = "tag1" , tag = "tag2"

use:

select * task bring together tasktag on task.task_id = tasktag.task_id bring together tag on tasktag.tag_id = tag.tag_id tag in ('tag1', 'tag2') grouping task.task_id having count(distinct tag) = 2

the having count(distinct ...) needs equal number of in parameters, or risk seeing false positives (ie duplicates of tag1 count 2, etc).

sql sqlite

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