Spaarsh commented on issue #14203: URL: https://github.com/apache/datafusion/issues/14203#issuecomment-2603032819
This is what I have added to the documentation. For all the existing operators, single examples sufficed since they followed a "one-way" comparison. While the spaceship operator is a three-way comparation. If this seems excessive, please let me know! --- (op_spaceship)= ### `<=>` Three-way comparision operator. A NULL-safe operator that returns true if both operands are equal or both are NULL, false otherwise. ```sql > SELECT NULL <=> NULL; +--------------------------------+ | NULL IS NOT DISTINCT FROM NULL | +--------------------------------+ | true | +--------------------------------+ ``` ```sql > SELECT 1 <=> NULL; +------------------------------------+ | Int64(1) IS NOT DISTINCT FROM NULL | +------------------------------------+ | false | +------------------------------------+ ``` ```sql > SELECT 1 <=> 2; +----------------------------------------+ | Int64(1) IS NOT DISTINCT FROM Int64(2) | +----------------------------------------+ | false | +----------------------------------------+ ``` ```sql > SELECT 1 <=> 1; +----------------------------------------+ | Int64(1) IS NOT DISTINCT FROM Int64(1) | +----------------------------------------+ | true | +----------------------------------------+ ``` --- I would also like to suggest that for the sake of clarity, we ensure that the description of the Spaceship operator is the similar to that of ```IS DISTINCT FROM```. The documentation for ```IS DISTINCT FROM`` says this in the description: ```Guarantees the result of a comparison is `true` or `false` and not an empty set``` So the description for the Spaceship Operator becomes: ```Three-way comparison operator. Guarantees the result of a comparison is `true` or `false` and not an empty set.``` But I feel this explanation to be lacking. Hence my suggestion is to change the description of ```IS DISTINCT FROM`` to the one I have chosen for the Spaceship operator. Hence, the description for ```IS DISTINCT FROM``` would become: ```A NULL-safe operator that returns false if both operands are equal or both are NULL, true otherwise.``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org
