A lot of time we see that there are lack on the OOTB functions, for these we can obviously use SQL formula but an OOTB function will be always good.
1. Take hour, minute and second part from a datetime by using a single function.
2. Provide "Regular Expression" function to find a pattern of string.
3. In the Operator section of query, there is no "Ends with" option, we may use "Contains" but that will not always return the desired result.
You can expand them by yourself for your needs check the link:
Adding additional SQL functions
Or create xtk:option XtkPassUnknownSQLFunctionsToRDBMS, set to 1.