[CP] implement preserve order for pagination

src/sql/resolver/dml/ob_hint.cpp

@@ -818,6 +818,11 @@ bool ObOptParamHint::is_param_val_valid(const OptParamType param_type, const ObO
                                       || 0 == val.get_varchar().case_compare("false"));
       break;
     }
+    case PRESERVE_ORDER_FOR_PAGINATION: {
+      is_valid = val.is_varchar() && (0 == val.get_varchar().case_compare("true")
+                                      || 0 == val.get_varchar().case_compare("false"));
+      break;
+    }
     default:
       LOG_TRACE("invalid opt param val", K(param_type), K(val));
       break;

src/sql/resolver/dml/ob_hint.h

@@ -108,6 +108,7 @@ struct ObOptParamHint
     DEF(WORKAREA_SIZE_POLICY,)         \
     DEF(ENABLE_RICH_VECTOR_FORMAT,)    \
     DEF(_ENABLE_STORAGE_CARDINALITY_ESTIMATION,)   \
+    DEF(PRESERVE_ORDER_FOR_PAGINATION,)   \
 
   DECLARE_ENUM(OptParamType, opt_param, OPT_PARAM_TYPE_DEF, static);