INSERT Failed. 3800: Datatype Mismatch in THEN/ELSE expression

Question

INSERT Failed. 3800: Datatype Mismatch in THEN/ELSE expression. i'm facing this error in SQL tera data

Answer 1

You have the issue with your last case expression, both the valies (then and else) must be of same data type:

case
  when ModifiedDate='NULL' 
  then 'n/a' -- this is char
  else cast (ModifiedDate as date format'yyyy-mm-dd') -- this is date
end as ModifiedDate

You should think about replacing n/a with some valid date or null.