Please add support for SQL COALESCE
While U-SQL is using C# as an expression language, there are some expressions in SQL that are cumbersome to write in C#. Please add support for COALESCE (https://msdn.microsoft.com/en-us/library/ms190349.aspx) to U-SQL similar to how you have added LIKE.
David Paul Giroux commented
Please see [COALESCE (Transact-SQL) and ??](https://msdn.microsoft.com/en-us/library/azure/mt771654.aspx#coalesce) which provides an example of using ?? in lieu of COALESCE.