presto-main/src/main/java/io/prestosql/metadata/ProcedureRegistry.java/ProcedureRegistry/addProcedures
class ProcedureRegistry:    public void addProcedures(CatalogName catalogName, Collection<Procedure> procedures)
    {
        requireNonNull(catalogName, "catalogName is null");
        requireNonNull(procedures, "procedures is null");

        procedures.forEach(this::validateProcedure);

        Map<SchemaTableName, Procedure> proceduresByName = Maps.uniqueIndex(
                procedures,
                procedure -> new SchemaTableName(procedure.getSchema(), procedure.getName()));

        checkState(connectorProcedures.putIfAbsent(catalogName, proceduresByName) == null, "Procedures already registered for connector: %s", catalogName);
    }