The service flow project tools support a subset of the ESQL functionality that is provided in WebSphere® Message Broker (see ESQL reference).
The service flow project tools do not support ESQL in two specific contexts (see Limitations on features and capabilities when generating HATS macros or when playing flows).
The current level of the service flow project tools uses ESQL expressions instead of ESQL modules and .esql files (see Using ESQL expressions instead of ESQL modules).