SQL Server - 在WHERE子句中使用谓词的替代方法

Question

I would like to delete all of the events in my DemoTable where the difference between the first event and last event for that interaction is greater than 30 minutes. I wrote a select statement to look at all of these events and used the HAVING keyword to get the events that have a DATEDIFF of greater than 30 minutes.

Since I can't use a HAVING in a delete or use a predicate in a WHERE clause, what is the best alternative/proper way to do what I want to do in the incorrect code below...

DELETE
FROM dbo.DemoTable dt
WHERE DATEDIFF(MINUTE, MIN(dt.utc), MAX(dt.utc)) > 30
GROUP BY dt.interactionId;
GO

EDIT: Thank you to everyone for their suggestions!

Answer 1

A quick and dirty way is like this:

DELETE FROM
    dbo.DemoTable
WHERE
    dto.DemoTable.YourPrimaryKey IN
    (
        SELECT
            YourPrimaryKey
        FROM
            -- your query here
    )

This only works for non-composite primary-keys.

Answer 2

I think one of the alternative is to use a temptable containing the valid data and use those data to eliminate invalid ones like below:

SELECT dt.interactionid
INTO #temp
FROM DemoTable dt
WHERE DATEDIFF(MINUTE, MIN(dt.utc), MAX(dt.utc)) <= 30

DELETE dt
FROM DemoTable dt
WHERE NOT EXISTS (select * from #temp t where t.interactionid = dt.interactionid)

Answer 3

A sub query?

delete from dbo.demotable
where interactionid in 
    (select dt.interactionid
    from dbo.demotable dt
    WHERE DATEDIFF(MINUTE, MIN(dt.utc), MAX(dt.utc)) > 30
    GROUP BY dt.interactionId)

depending on the version of sql you could just delete it like so:

delete from dt
from dbo.demotable dt
WHERE DATEDIFF(MINUTE, MIN(dt.utc), MAX(dt.utc)) > 30

Answer 4

If you want to remove all such interactions, you can use a join or an updatable CTE. I would go for the latter:

with todelete as (
      select dt.*, 
             min(dt.utc) over (partition by dt.interactionId) as min_utc,
             max(dt.utc) over (partition by dt.interactionId) as max_utc
      from dbo.DemoTable dt
     )
delete from todelete
    where datediff(day, min_utc, max_utc) > 30;

Answer 5

You can use subqueries

DELETE FROM dbo.DemoTable dt
WHERE id IN (
    SELECT id FROM dbo.DemoTable
    -- The rest of your query
)
GO