BRF+ function for Validations

Hi Experts,

I am new to BRF+ Engine to define the validations and derivations. I have a requirement to do certain validatins for an entity type. I could create a CHECK function for this entity type with the naming convention as CHECK_ENTITYTYPE. I could see in the BRF+ CHECK function, there is a provision to include only RULESETS. I have a requirement to do validations against certain data base tables for the same entity types. I created data base look up tables for this.

Please guide how to include data base look ups and the formulas for the entity type in the CHECK function of that entity type.

Thanks,

Sapna