TRY_CAST in SQL Server: convert without blowing up

CAST on a dirty column stops the whole query at the first bad value. TRY_CAST returns NULL for that row and keeps going. That is what you want on an import.

A messy quantity

SELECT product_name,
       TRY_CAST(raw_qty AS int) AS qty
FROM ImportLines;

Rows that say “n/a” become NULL qty. You can find them with WHERE TRY_CAST(raw_qty AS int) IS NULL AND raw_qty IS NOT NULL.