filter

The filter formula to use to find existing matching rows to update. The formula needs to return zero or more rows. If the formula returns 0 rows, then a new row will be appended in the target table. If the formula returns one or more rows, then the returned rows will be updated.

Note that the filter formula needs to return rows from the target table for the upsert operation to succeed. If the filter formula has a syntax error or it doesn't evaluate to zero or more rows in the target table for any one item in the input list, then the entire BatchUpsertTableRows request fails and no updates are made to the table.