The “==” is using the equals methods which checks if the two references point to the same object. The definition of “===” depends on the context/object. For Spark , “===” is using the equalTo method.
See
- for
==https://spark.apache.org/docs/2.0.0/api/java/org/apache/spark/sql/Column.html#equals(java.lang.Object) - for
===
https://spark.apache.org/docs/2.0.0/api/java/org/apache/spark/sql/Column.html#equalTo(java.lang.Object)
(Since you are referencing Spark:) An important difference for Spark is the return value. For Column:
-
==returns a boolean -
===returns a column (which contains the result of the comparisons of the elements of two columns)