lead(input[, offset[, default]]) – Returns the value of `input` at the `offset`th row after the current row in the window. The default value of `offset` is 1 and the default value of `default` is null. If the value of `input` at the `offset`th row is null, null is returned. If there is no such an offset row (e.g., when the offset is 1, the last row of the window does not have any subsequent row), `default` is returned.
Platforms: WhereOS, Spark, Hive
Class: org.apache.spark.sql.catalyst.expressions.Lead
More functions can be added to WhereOS via Python or R bindings or as Java & Scala UDF (user-defined function), UDAF (user-defined aggregation function) and UDTF (user-defined table generating function) extensions. Custom libraries can be added on via Settings-page or installed from WhereOS Store.
