[CP] 【SQLancer】query result mismatch

src/sql/engine/expr/ob_expr_operator.cpp

@@ -202,13 +202,19 @@ int OB_INLINE ObExprOperator::cast_operand_type(
     LOG_DEBUG(
         "need cast operand", K(res_type), K(res_type.get_calc_meta().get_scale()), K(res_obj), K(res_obj.get_scale()));
     ObCastMode cast_mode = get_cast_mode();
-    // In PAD expression, we need add COLUMN_CONVERT to cast mode when cast is
-    // from bit to binary and column convert is set in column_conv_ctx_. The COLUMN_CONVERT
-    // cast mode is used in bit_to_string to decide which cast way is appropriate.
+
     if (OB_UNLIKELY(T_FUN_PAD == get_type() && ob_is_bit_tc(param_type) &&
                     ob_is_varbinary_type(calc_type, calc_collation_type) &&
                     CM_IS_COLUMN_CONVERT(expr_ctx.column_conv_ctx_.cast_mode_))) {
+      // In PAD expression, we need add COLUMN_CONVERT to cast mode when cast is
+      // from bit to binary and column convert is set in column_conv_ctx_. The COLUMN_CONVERT
+      // cast mode is used in bit_to_string to decide which cast way is appropriate.
       cast_mode |= CM_COLUMN_CONVERT;
+    } else if (OB_UNLIKELY(T_FUN_SYS_BIT_COUNT == get_type() && ObIntType == param_type && ObUInt64Type == calc_type)) {
+      // when param_type is ObIntType and calc_type is ObUInt64Type,
+      // set CM_NO_RANGE_CHECK in cast_mode,
+      // so that res_obj will not convert to zero even res_obj is less than 0.
+      cast_mode |= CM_NO_RANGE_CHECK;
     }
 
     bool is_bool = false;