There is an SAP ABAP standard table that I'm trying to access in SAPUI5. I have created an RFC. How do I use this RFC in SAPUI5 to get the data there without using NetWeaver Gateway?
I agree with Veera's answer and think that this is the best way of doing it without the Gateway when your application is deployed on the ABAP system (i.e. in the BSP repository). For completeness sake, I will also describe an alternative way of doing it if you are interested in exposing the application on the HANA Cloud Platform (HCP).
ABAP RFCs can be consumed through the HANA Cloud Connector (HCC) by HCP applications. So, if you would want to put your application in the HCP, then an idea would be to expose the RFC through the HCC, consume it e.g. in a Java application and the expose it to a UI5 app through this Java app (e.g. with a Servlet or a JAX-RS service). You can find an example of such a scenario in this repository and here you can find the SAP documentation about this.