Syntax Error In SQL Code

Question

I have faced with a strange syntax error plz help me to solve it.

WITH A as (
SELECT ambtemp,
       date_trunc('hour', dt)+
       CASE WHEN date_part('minute', dt) >= 30
            THEN interval '30 minutes'
            ELSE interval '0 minutes'
       END as t
FROM temm),

B as(
SELECT ambtemp,t,

       max(ambtemp::float(23)) OVER (PARTITION BY t) as max_temp,
       min(ambtemp::float(23)) OVER (PARTITION BY t) as min_temp
FROM A),


 H AS (
SELECT *      
FROM B
WHERE (max_temp - min_temp) <= 0.2 )

UPDATE temm
SET ambtemp = (NULL)
WHERE dt IN H

As you can see in the code, all the code ran properly except " WHERE dt IN H" and when I i ignore this part code runs but in the presence of the code I faced with following error:

ERROR:  syntax error at or near "H"
LINE 25: WHERE dt IN H
                     ^

Answer 1

try this:

UPDATE temm
SET ambtemp = (NULL)
WHERE dt IN ( SELECT ambtemp FROM H )