instance method exec_query

# File activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb, line 54
        def exec_query(sql, name = "SQL", binds = [], prepare: false)
          execute_and_clear(sql, name, binds, prepare: prepare) do |result|
            types = {}
            fields = result.fields
            fields.each_with_index do |fname, i|
              ftype = result.ftype i
              fmod  = result.fmod i
              case type = get_oid_type(ftype, fmod, fname)
              when Type::Integer, Type::Float, OID::Decimal, Type::String, Type::DateTime, Type::Boolean
                # skip if a column has already been type casted by pg decoders
              else types[fname] = type
              end
            end
            build_result(columns: fields, rows: result.values, column_types: types)
          end
        end