I split my input data, with two selects with different where clauses, I then want to join them back together after some aggregation, with a left outer join.
This works fine, and the joined data from the left table have null values as expected. This would be okay if I could do a IsNull(lefttable.column,0), but IsNull is not supported as far as I can see, is there any alternative way to structure my statement?
You can use "IS NULL" operator (same as in TSQL)
If you want to project it as a column value you can use this expression
CASE WHEN lefttable.column IS NULL THEN 1 ELSE 0 END AS isNull