diff --git a/src/promql/src/extension_plan/empty_metric.rs b/src/promql/src/extension_plan/empty_metric.rs
index f4c33cf30f63..74d25d8ebb8f 100644
--- a/src/promql/src/extension_plan/empty_metric.rs
+++ b/src/promql/src/extension_plan/empty_metric.rs
@@ -104,8 +104,8 @@ impl EmptyMetric {
             .map(|expr| {
                 physical_planner.create_physical_expr(
                     expr,
-                    &self.result_schema,
-                    &ArrowSchema::from(self.result_schema.as_ref()),
+                    &self.time_index_schema,
+                    &ArrowSchema::from(self.time_index_schema.as_ref()),
                     session_state,
                 )
             })
diff --git a/src/promql/src/planner.rs b/src/promql/src/planner.rs
index e8d9d79bc6d5..17d222c2aa58 100644
--- a/src/promql/src/planner.rs
+++ b/src/promql/src/planner.rs
@@ -77,6 +77,10 @@ const DEFAULT_FIELD_COLUMN: &str = "value";
 /// Special modifier to project field columns under multi-field mode
 const FIELD_COLUMN_MATCHER: &str = "__field__";
 
+/// default value column name for prometheus metrics.
+/// This is the same with the constant defined in `servers`
+const GREPTIME_VALUE: &str = "greptime_value";
+
 #[derive(Default, Debug, Clone)]
 struct PromPlannerContext {
     // query parameters
@@ -292,13 +296,13 @@ impl PromPlanner {
                         let left_field_columns = self.ctx.field_columns.clone();
                         let left_table_ref: OwnedTableReference =
                             self.ctx.table_name.clone().unwrap_or_default().into();
-                        let left_tag_cols = self.ctx.tag_columns.clone();
+                        let left_context = self.ctx.clone();
 
                         let right_input = self.prom_expr_to_plan(*rhs.clone()).await?;
                         let right_field_columns = self.ctx.field_columns.clone();
                         let right_table_ref: OwnedTableReference =
                             self.ctx.table_name.clone().unwrap_or_default().into();
-                        let right_tag_cols = self.ctx.tag_columns.clone();
+                        let right_context = self.ctx.clone();
 
                         // TODO(ruihang): avoid join if left and right are the same table
 
@@ -307,8 +311,8 @@ impl PromPlanner {
                             return self.set_op_on_non_field_columns(
                                 left_input,
                                 right_input,
-                                left_tag_cols,
-                                right_tag_cols,
+                                left_context,
+                                right_context,
                                 *op,
                                 modifier,
                             );
@@ -1333,6 +1337,8 @@ impl PromPlanner {
         // reuse `SPECIAL_TIME_FUNCTION` as name of time index column
         self.ctx.time_index_column = Some(SPECIAL_TIME_FUNCTION.to_string());
         self.ctx.table_name = Some(String::new());
+        self.ctx.tag_columns = vec![];
+        self.ctx.field_columns = vec![GREPTIME_VALUE.to_string()];
         Ok(LogicalPlan::Extension(Extension {
             node: Arc::new(
                 EmptyMetric::new(
@@ -1340,7 +1346,7 @@ impl PromPlanner {
                     self.ctx.end,
                     self.ctx.interval,
                     SPECIAL_TIME_FUNCTION.to_string(),
-                    DEFAULT_FIELD_COLUMN.to_string(),
+                    GREPTIME_VALUE.to_string(),
                     Some(DfExpr::Literal(ScalarValue::Float64(Some(lit)))),
                 )
                 .context(DataFusionPlanningSnafu)?,
@@ -1536,19 +1542,35 @@ impl PromPlanner {
 
     /// Build a set operator (AND/OR/UNLESS)
     fn set_op_on_non_field_columns(
-        &self,
+        &mut self,
         left: LogicalPlan,
         right: LogicalPlan,
-        left_tag_cols: Vec<String>,
-        right_tag_cols: Vec<String>,
+        left_context: PromPlannerContext,
+        right_context: PromPlannerContext,
         op: TokenType,
         modifier: &Option<BinModifier>,
     ) -> Result<LogicalPlan> {
-        let mut left_tag_col_set = left_tag_cols.into_iter().collect::<HashSet<_>>();
-        let mut right_tag_col_set = right_tag_cols.into_iter().collect::<HashSet<_>>();
+        let mut left_tag_col_set = left_context
+            .tag_columns
+            .iter()
+            .cloned()
+            .collect::<HashSet<_>>();
+        let mut right_tag_col_set = right_context
+            .tag_columns
+            .iter()
+            .cloned()
+            .collect::<HashSet<_>>();
 
         if matches!(op.id(), token::T_LOR) {
-            return self.or_operator(left, right, left_tag_col_set, right_tag_col_set, modifier);
+            return self.or_operator(
+                left,
+                right,
+                left_tag_col_set,
+                right_tag_col_set,
+                left_context,
+                right_context,
+                modifier,
+            );
         }
 
         // apply modifier
@@ -1630,19 +1652,22 @@ impl PromPlanner {
                 .build()
                 .context(DataFusionPlanningSnafu),
             token::T_LOR => {
-                self.or_operator(left, right, left_tag_col_set, right_tag_col_set, modifier)
+                unreachable!()
             }
             _ => UnexpectedTokenSnafu { token: op }.fail(),
         }
     }
 
     // TODO(ruihang): change function name
+    #[allow(clippy::too_many_arguments)]
     fn or_operator(
-        &self,
+        &mut self,
         left: LogicalPlan,
         right: LogicalPlan,
         left_tag_cols_set: HashSet<String>,
         right_tag_cols_set: HashSet<String>,
+        left_context: PromPlannerContext,
+        right_context: PromPlannerContext,
         modifier: &Option<BinModifier>,
     ) -> Result<LogicalPlan> {
         // prepare hash sets
@@ -1668,18 +1693,37 @@ impl PromPlanner {
             .as_ref()
             .map(|r| r.to_string())
             .unwrap_or_default();
+        let left_time_index_column =
+            left_context
+                .time_index_column
+                .clone()
+                .with_context(|| TimeIndexNotFoundSnafu {
+                    table: left_qualifier_string.clone(),
+                })?;
+        let right_time_index_column =
+            right_context
+                .time_index_column
+                .clone()
+                .with_context(|| TimeIndexNotFoundSnafu {
+                    table: right_qualifier_string.clone(),
+                })?;
 
         // step 0: fill all columns in output schema
-        let all_columns_set = left
+        let mut all_columns_set = left
             .schema()
             .fields()
             .iter()
             .chain(right.schema().fields().iter())
             .map(|field| field.name().clone())
             .collect::<HashSet<_>>();
+        // remove time index column
+        all_columns_set.remove(&left_time_index_column);
+        all_columns_set.remove(&right_time_index_column);
         let mut all_columns = all_columns_set.into_iter().collect::<Vec<_>>();
         // sort to ensure the generated schema is not volatile
         all_columns.sort_unstable();
+        // use left time index column name as the result time index column name
+        all_columns.insert(0, left_time_index_column.clone());
 
         // step 1: align schema using project, fill non-exist columns with null
         let left_proj_exprs = all_columns.iter().map(|col| {
@@ -1689,13 +1733,21 @@ impl PromPlanner {
                 DfExpr::Column(Column::new(left_qualifier.clone(), col))
             }
         });
-        let right_proj_exprs = all_columns.iter().map(|col| {
+        let right_time_index_expr = DfExpr::Column(Column::new(
+            right_qualifier.clone(),
+            right_time_index_column,
+        ))
+        .alias(left_time_index_column.clone());
+        let right_proj_exprs_without_time_index = all_columns.iter().skip(1).map(|col| {
             if tags_not_in_right.contains(col) {
                 DfExpr::Literal(ScalarValue::Utf8(None)).alias(col.to_string())
             } else {
                 DfExpr::Column(Column::new(right_qualifier.clone(), col))
             }
         });
+        let right_proj_exprs = [right_time_index_expr]
+            .into_iter()
+            .chain(right_proj_exprs_without_time_index);
 
         let left_projected = LogicalPlanBuilder::from(left)
             .project(left_proj_exprs)
@@ -1736,13 +1788,17 @@ impl PromPlanner {
             left_projected,
             right_projected,
             match_columns,
-            self.ctx.time_index_column.clone().unwrap(),
+            left_time_index_column.clone(),
             schema,
         );
         let result = LogicalPlan::Extension(Extension {
             node: Arc::new(union_distinct_on),
         });
 
+        // step 4: update context
+        self.ctx.time_index_column = Some(left_time_index_column);
+        self.ctx.tag_columns = all_tags.into_iter().collect();
+
         Ok(result)
     }
 
diff --git a/tests/cases/standalone/common/promql/set_operation.result b/tests/cases/standalone/common/promql/set_operation.result
index 15a7a865a317..31a0a6638fd7 100644
--- a/tests/cases/standalone/common/promql/set_operation.result
+++ b/tests/cases/standalone/common/promql/set_operation.result
@@ -6,7 +6,7 @@ create table http_requests (
     job string,
     instance string,
     g string, -- for `group`
-    val double,
+    greptime_value double,
     primary key (job, instance, g)
 );
 
@@ -32,7 +32,7 @@ Affected Rows: 0
 create table vector_matching_a(
     ts timestamp time index,
     l string primary key,
-    val double,
+    greptime_value double,
 );
 
 Affected Rows: 0
@@ -49,12 +49,12 @@ Affected Rows: 2
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') http_requests{g="canary"} and http_requests{instance="0"};
 
-+---------------------+-----+----------+--------+-------+
-| ts                  | job | instance | g      | val   |
-+---------------------+-----+----------+--------+-------+
-| 1970-01-01T00:50:00 | api | 0        | canary | 300.0 |
-| 1970-01-01T00:50:00 | app | 0        | canary | 700.0 |
-+---------------------+-----+----------+--------+-------+
++---------------------+-----+----------+--------+----------------+
+| ts                  | job | instance | g      | greptime_value |
++---------------------+-----+----------+--------+----------------+
+| 1970-01-01T00:50:00 | api | 0        | canary | 300.0          |
+| 1970-01-01T00:50:00 | app | 0        | canary | 700.0          |
++---------------------+-----+----------+--------+----------------+
 
 -- eval instant at 50m (http_requests{group="canary"} + 1) and http_requests{instance="0"}
 -- 	{group="canary", instance="0", job="api-server"} 301
@@ -62,12 +62,12 @@ tql eval (3000, 3000, '1s') http_requests{g="canary"} and http_requests{instance
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and http_requests{instance="0"};
 
-+-----+----------+--------+---------------------+------------------+
-| job | instance | g      | ts                  | val + Float64(1) |
-+-----+----------+--------+---------------------+------------------+
-| api | 0        | canary | 1970-01-01T00:50:00 | 301.0            |
-| app | 0        | canary | 1970-01-01T00:50:00 | 701.0            |
-+-----+----------+--------+---------------------+------------------+
++-----+----------+--------+---------------------+-----------------------------+
+| job | instance | g      | ts                  | greptime_value + Float64(1) |
++-----+----------+--------+---------------------+-----------------------------+
+| api | 0        | canary | 1970-01-01T00:50:00 | 301.0                       |
+| app | 0        | canary | 1970-01-01T00:50:00 | 701.0                       |
++-----+----------+--------+---------------------+-----------------------------+
 
 -- eval instant at 50m (http_requests{group="canary"} + 1) and on(instance, job) http_requests{instance="0", group="production"}
 -- 	{group="canary", instance="0", job="api-server"} 301
@@ -75,12 +75,12 @@ tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and http_requests{in
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and on(instance, job) http_requests{instance="0", g="production"};
 
-+-----+----------+--------+---------------------+------------------+
-| job | instance | g      | ts                  | val + Float64(1) |
-+-----+----------+--------+---------------------+------------------+
-| api | 0        | canary | 1970-01-01T00:50:00 | 301.0            |
-| app | 0        | canary | 1970-01-01T00:50:00 | 701.0            |
-+-----+----------+--------+---------------------+------------------+
++-----+----------+--------+---------------------+-----------------------------+
+| job | instance | g      | ts                  | greptime_value + Float64(1) |
++-----+----------+--------+---------------------+-----------------------------+
+| api | 0        | canary | 1970-01-01T00:50:00 | 301.0                       |
+| app | 0        | canary | 1970-01-01T00:50:00 | 701.0                       |
++-----+----------+--------+---------------------+-----------------------------+
 
 -- eval instant at 50m (http_requests{group="canary"} + 1) and on(instance) http_requests{instance="0", group="production"}
 -- 	{group="canary", instance="0", job="api-server"} 301
@@ -88,12 +88,12 @@ tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and on(instance, job
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and on(instance) http_requests{instance="0", g="production"};
 
-+-----+----------+--------+---------------------+------------------+
-| job | instance | g      | ts                  | val + Float64(1) |
-+-----+----------+--------+---------------------+------------------+
-| api | 0        | canary | 1970-01-01T00:50:00 | 301.0            |
-| app | 0        | canary | 1970-01-01T00:50:00 | 701.0            |
-+-----+----------+--------+---------------------+------------------+
++-----+----------+--------+---------------------+-----------------------------+
+| job | instance | g      | ts                  | greptime_value + Float64(1) |
++-----+----------+--------+---------------------+-----------------------------+
+| api | 0        | canary | 1970-01-01T00:50:00 | 301.0                       |
+| app | 0        | canary | 1970-01-01T00:50:00 | 701.0                       |
++-----+----------+--------+---------------------+-----------------------------+
 
 -- eval instant at 50m (http_requests{group="canary"} + 1) and ignoring(group) http_requests{instance="0", group="production"}
 -- 	{group="canary", instance="0", job="api-server"} 301
@@ -101,12 +101,12 @@ tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and on(instance) htt
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and ignoring(g) http_requests{instance="0", g="production"};
 
-+-----+----------+--------+---------------------+------------------+
-| job | instance | g      | ts                  | val + Float64(1) |
-+-----+----------+--------+---------------------+------------------+
-| api | 0        | canary | 1970-01-01T00:50:00 | 301.0            |
-| app | 0        | canary | 1970-01-01T00:50:00 | 701.0            |
-+-----+----------+--------+---------------------+------------------+
++-----+----------+--------+---------------------+-----------------------------+
+| job | instance | g      | ts                  | greptime_value + Float64(1) |
++-----+----------+--------+---------------------+-----------------------------+
+| api | 0        | canary | 1970-01-01T00:50:00 | 301.0                       |
+| app | 0        | canary | 1970-01-01T00:50:00 | 701.0                       |
++-----+----------+--------+---------------------+-----------------------------+
 
 -- eval instant at 50m (http_requests{group="canary"} + 1) and ignoring(group, job) http_requests{instance="0", group="production"}
 -- 	{group="canary", instance="0", job="api-server"} 301
@@ -114,12 +114,12 @@ tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and ignoring(g) http
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and ignoring(g, job) http_requests{instance="0", g="production"};
 
-+-----+----------+--------+---------------------+------------------+
-| job | instance | g      | ts                  | val + Float64(1) |
-+-----+----------+--------+---------------------+------------------+
-| api | 0        | canary | 1970-01-01T00:50:00 | 301.0            |
-| app | 0        | canary | 1970-01-01T00:50:00 | 701.0            |
-+-----+----------+--------+---------------------+------------------+
++-----+----------+--------+---------------------+-----------------------------+
+| job | instance | g      | ts                  | greptime_value + Float64(1) |
++-----+----------+--------+---------------------+-----------------------------+
+| api | 0        | canary | 1970-01-01T00:50:00 | 301.0                       |
+| app | 0        | canary | 1970-01-01T00:50:00 | 701.0                       |
++-----+----------+--------+---------------------+-----------------------------+
 
 -- eval instant at 50m http_requests{group="canary"} or http_requests{group="production"}
 -- 	http_requests{group="canary", instance="0", job="api-server"} 300
@@ -133,18 +133,18 @@ tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) and ignoring(g, job)
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') http_requests{g="canary"} or http_requests{g="production"};
 
-+------------+----------+-----+---------------------+-------+
-| g          | instance | job | ts                  | val   |
-+------------+----------+-----+---------------------+-------+
-| canary     | 0        | api | 1970-01-01T00:50:00 | 300.0 |
-| canary     | 0        | app | 1970-01-01T00:50:00 | 700.0 |
-| canary     | 1        | api | 1970-01-01T00:50:00 | 400.0 |
-| canary     | 1        | app | 1970-01-01T00:50:00 | 800.0 |
-| production | 0        | api | 1970-01-01T00:50:00 | 100.0 |
-| production | 0        | app | 1970-01-01T00:50:00 | 500.0 |
-| production | 1        | api | 1970-01-01T00:50:00 | 200.0 |
-| production | 1        | app | 1970-01-01T00:50:00 | 600.0 |
-+------------+----------+-----+---------------------+-------+
++---------------------+------------+----------------+----------+-----+
+| ts                  | g          | greptime_value | instance | job |
++---------------------+------------+----------------+----------+-----+
+| 1970-01-01T00:50:00 | canary     | 300.0          | 0        | api |
+| 1970-01-01T00:50:00 | canary     | 400.0          | 1        | api |
+| 1970-01-01T00:50:00 | canary     | 700.0          | 0        | app |
+| 1970-01-01T00:50:00 | canary     | 800.0          | 1        | app |
+| 1970-01-01T00:50:00 | production | 100.0          | 0        | api |
+| 1970-01-01T00:50:00 | production | 200.0          | 1        | api |
+| 1970-01-01T00:50:00 | production | 500.0          | 0        | app |
+| 1970-01-01T00:50:00 | production | 600.0          | 1        | app |
++---------------------+------------+----------------+----------+-----+
 
 -- # On overlap the rhs samples must be dropped.
 -- eval instant at 50m (http_requests{group="canary"} + 1) or http_requests{instance="1"}
@@ -157,7 +157,7 @@ tql eval (3000, 3000, '1s') http_requests{g="canary"} or http_requests{g="produc
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) or http_requests{instance="1"};
 
-Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named http_requests.val. Valid fields are http_requests.job, http_requests.instance, http_requests.g, http_requests.ts, "val + Float64(1)".
+Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named http_requests.greptime_value. Valid fields are http_requests.job, http_requests.instance, http_requests.g, http_requests.ts, "greptime_value + Float64(1)".
 
 -- # Matching only on instance excludes everything that has instance=0/1 but includes
 -- # entries without the instance label.
@@ -172,7 +172,7 @@ Error: 1004(InvalidArguments), Internal error during building DataFusion plan: N
 -- NOT SUPPORTED: `or`
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) or on(instance) (http_requests or cpu_count or vector_matching_a);
 
-Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named cpu_count.val. Valid fields are cpu_count.ts.
+Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named cpu_count.greptime_value. Valid fields are cpu_count.ts.
 
 -- eval instant at 50m (http_requests{group="canary"} + 1) or ignoring(l, group, job) (http_requests or cpu_count or vector_matching_a)
 -- 	{group="canary", instance="0", job="api-server"} 301
@@ -185,7 +185,7 @@ Error: 1004(InvalidArguments), Internal error during building DataFusion plan: N
 -- NOT SUPPORTED: `or`
 tql eval (3000, 3000, '1s') (http_requests{g="canary"} + 1) or ignoring(l, g, job) (http_requests or cpu_count or vector_matching_a);
 
-Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named cpu_count.val. Valid fields are cpu_count.ts.
+Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named cpu_count.greptime_value. Valid fields are cpu_count.ts.
 
 -- eval instant at 50m http_requests{group="canary"} unless http_requests{instance="0"}
 -- 	http_requests{group="canary", instance="1", job="api-server"} 400
@@ -193,12 +193,12 @@ Error: 1004(InvalidArguments), Internal error during building DataFusion plan: N
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') http_requests{g="canary"} unless http_requests{instance="0"};
 
-+---------------------+-----+----------+--------+-------+
-| ts                  | job | instance | g      | val   |
-+---------------------+-----+----------+--------+-------+
-| 1970-01-01T00:50:00 | api | 1        | canary | 400.0 |
-| 1970-01-01T00:50:00 | app | 1        | canary | 800.0 |
-+---------------------+-----+----------+--------+-------+
++---------------------+-----+----------+--------+----------------+
+| ts                  | job | instance | g      | greptime_value |
++---------------------+-----+----------+--------+----------------+
+| 1970-01-01T00:50:00 | api | 1        | canary | 400.0          |
+| 1970-01-01T00:50:00 | app | 1        | canary | 800.0          |
++---------------------+-----+----------+--------+----------------+
 
 -- eval instant at 50m http_requests{group="canary"} unless on(job) http_requests{instance="0"}
 tql eval (3000, 3000, '1s') http_requests{g="canary"} unless on(job) http_requests{instance="0"};
@@ -212,12 +212,12 @@ tql eval (3000, 3000, '1s') http_requests{g="canary"} unless on(job) http_reques
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') http_requests{g="canary"} unless on(job, instance) http_requests{instance="0"};
 
-+---------------------+-----+----------+--------+-------+
-| ts                  | job | instance | g      | val   |
-+---------------------+-----+----------+--------+-------+
-| 1970-01-01T00:50:00 | api | 1        | canary | 400.0 |
-| 1970-01-01T00:50:00 | app | 1        | canary | 800.0 |
-+---------------------+-----+----------+--------+-------+
++---------------------+-----+----------+--------+----------------+
+| ts                  | job | instance | g      | greptime_value |
++---------------------+-----+----------+--------+----------------+
+| 1970-01-01T00:50:00 | api | 1        | canary | 400.0          |
+| 1970-01-01T00:50:00 | app | 1        | canary | 800.0          |
++---------------------+-----+----------+--------+----------------+
 
 -- eval instant at 50m http_requests{group="canary"} unless ignoring(group, instance) http_requests{instance="0"}
 tql eval (3000, 3000, '1s') http_requests{g="canary"} unless ignoring(g, instance) http_requests{instance="0"};
@@ -231,12 +231,12 @@ tql eval (3000, 3000, '1s') http_requests{g="canary"} unless ignoring(g, instanc
 -- SQLNESS SORT_RESULT 3 1
 tql eval (3000, 3000, '1s') http_requests{g="canary"} unless ignoring(g) http_requests{instance="0"};
 
-+---------------------+-----+----------+--------+-------+
-| ts                  | job | instance | g      | val   |
-+---------------------+-----+----------+--------+-------+
-| 1970-01-01T00:50:00 | api | 1        | canary | 400.0 |
-| 1970-01-01T00:50:00 | app | 1        | canary | 800.0 |
-+---------------------+-----+----------+--------+-------+
++---------------------+-----+----------+--------+----------------+
+| ts                  | job | instance | g      | greptime_value |
++---------------------+-----+----------+--------+----------------+
+| 1970-01-01T00:50:00 | api | 1        | canary | 400.0          |
+| 1970-01-01T00:50:00 | app | 1        | canary | 800.0          |
++---------------------+-----+----------+--------+----------------+
 
 -- # https://github.com/prometheus/prometheus/issues/1489
 -- eval instant at 50m http_requests AND ON (dummy) vector(1)
@@ -251,7 +251,7 @@ tql eval (3000, 3000, '1s') http_requests{g="canary"} unless ignoring(g) http_re
 -- NOT SUPPORTED: `vector()`
 tql eval (3000, 3000, '1s') http_requests AND ON (dummy) vector(1);
 
-Error: 1004(InvalidArguments), Unsupported expr type: vector
+Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named time. Valid fields are http_requests.ts, http_requests.job, http_requests.instance, http_requests.g, http_requests.greptime_value.
 
 -- eval instant at 50m http_requests AND IGNORING (group, instance, job) vector(1)
 -- 	http_requests{group="canary", instance="0", job="api-server"} 300
@@ -265,7 +265,7 @@ Error: 1004(InvalidArguments), Unsupported expr type: vector
 -- NOT SUPPORTED: `vector()`
 tql eval (3000, 3000, '1s') http_requests AND IGNORING (g, instance, job) vector(1);
 
-Error: 1004(InvalidArguments), Unsupported expr type: vector
+Error: 1004(InvalidArguments), Internal error during building DataFusion plan: No field named time. Valid fields are http_requests.ts, http_requests.job, http_requests.instance, http_requests.g, http_requests.greptime_value.
 
 drop table http_requests;
 
@@ -280,7 +280,7 @@ drop table vector_matching_a;
 Affected Rows: 0
 
 -- the following cases are not from Prometheus.
-create table t1 (ts timestamp time index, job string primary key, val double);
+create table t1 (ts timestamp time index, job string primary key, greptime_value double);
 
 Affected Rows: 0
 
@@ -288,7 +288,7 @@ insert into t1 values (0, "a", 1.0), (500000, "b", 2.0), (1000000, "a", 3.0), (1
 
 Affected Rows: 4
 
-create table t2 (ts timestamp time index, val double);
+create table t2 (ts timestamp time index, greptime_value double);
 
 Affected Rows: 0
 
@@ -299,102 +299,102 @@ Affected Rows: 7
 -- SQLNESS SORT_RESULT 3 1
 tql eval (0, 2000, '400') t1 or t2;
 
-+-----+---------------------+-----+
-| job | ts                  | val |
-+-----+---------------------+-----+
-|     | 1970-01-01T00:00:00 | 0.0 |
-|     | 1970-01-01T00:06:40 | 0.0 |
-|     | 1970-01-01T00:13:20 | 0.0 |
-|     | 1970-01-01T00:20:00 | 0.0 |
-|     | 1970-01-01T00:26:40 | 0.0 |
-|     | 1970-01-01T00:33:20 | 0.0 |
-| a   | 1970-01-01T00:00:00 | 1.0 |
-| a   | 1970-01-01T00:20:00 | 3.0 |
-| b   | 1970-01-01T00:13:20 | 2.0 |
-| c   | 1970-01-01T00:26:40 | 4.0 |
-+-----+---------------------+-----+
++---------------------+----------------+-----+
+| ts                  | greptime_value | job |
++---------------------+----------------+-----+
+| 1970-01-01T00:00:00 | 0.0            |     |
+| 1970-01-01T00:00:00 | 1.0            | a   |
+| 1970-01-01T00:06:40 | 0.0            |     |
+| 1970-01-01T00:13:20 | 0.0            |     |
+| 1970-01-01T00:13:20 | 2.0            | b   |
+| 1970-01-01T00:20:00 | 0.0            |     |
+| 1970-01-01T00:20:00 | 3.0            | a   |
+| 1970-01-01T00:26:40 | 0.0            |     |
+| 1970-01-01T00:26:40 | 4.0            | c   |
+| 1970-01-01T00:33:20 | 0.0            |     |
++---------------------+----------------+-----+
 
 -- SQLNESS SORT_RESULT 3 1
 tql eval (0, 2000, '400') t1 or on () t2;
 
-+-----+---------------------+-----+
-| job | ts                  | val |
-+-----+---------------------+-----+
-|     | 1970-01-01T00:06:40 | 0.0 |
-|     | 1970-01-01T00:33:20 | 0.0 |
-| a   | 1970-01-01T00:00:00 | 1.0 |
-| a   | 1970-01-01T00:20:00 | 3.0 |
-| b   | 1970-01-01T00:13:20 | 2.0 |
-| c   | 1970-01-01T00:26:40 | 4.0 |
-+-----+---------------------+-----+
++---------------------+----------------+-----+
+| ts                  | greptime_value | job |
++---------------------+----------------+-----+
+| 1970-01-01T00:00:00 | 1.0            | a   |
+| 1970-01-01T00:06:40 | 0.0            |     |
+| 1970-01-01T00:13:20 | 2.0            | b   |
+| 1970-01-01T00:20:00 | 3.0            | a   |
+| 1970-01-01T00:26:40 | 4.0            | c   |
+| 1970-01-01T00:33:20 | 0.0            |     |
++---------------------+----------------+-----+
 
 -- SQLNESS SORT_RESULT 3 1
 tql eval (0, 2000, '400') t1 or on (job) t2;
 
-+-----+---------------------+-----+
-| job | ts                  | val |
-+-----+---------------------+-----+
-|     | 1970-01-01T00:00:00 | 0.0 |
-|     | 1970-01-01T00:06:40 | 0.0 |
-|     | 1970-01-01T00:13:20 | 0.0 |
-|     | 1970-01-01T00:20:00 | 0.0 |
-|     | 1970-01-01T00:26:40 | 0.0 |
-|     | 1970-01-01T00:33:20 | 0.0 |
-| a   | 1970-01-01T00:00:00 | 1.0 |
-| a   | 1970-01-01T00:20:00 | 3.0 |
-| b   | 1970-01-01T00:13:20 | 2.0 |
-| c   | 1970-01-01T00:26:40 | 4.0 |
-+-----+---------------------+-----+
++---------------------+----------------+-----+
+| ts                  | greptime_value | job |
++---------------------+----------------+-----+
+| 1970-01-01T00:00:00 | 0.0            |     |
+| 1970-01-01T00:00:00 | 1.0            | a   |
+| 1970-01-01T00:06:40 | 0.0            |     |
+| 1970-01-01T00:13:20 | 0.0            |     |
+| 1970-01-01T00:13:20 | 2.0            | b   |
+| 1970-01-01T00:20:00 | 0.0            |     |
+| 1970-01-01T00:20:00 | 3.0            | a   |
+| 1970-01-01T00:26:40 | 0.0            |     |
+| 1970-01-01T00:26:40 | 4.0            | c   |
+| 1970-01-01T00:33:20 | 0.0            |     |
++---------------------+----------------+-----+
 
 -- SQLNESS SORT_RESULT 3 1
 tql eval (0, 2000, '400') t2 or t1;
 
-+-----+---------------------+-----+
-| job | ts                  | val |
-+-----+---------------------+-----+
-|     | 1970-01-01T00:00:00 | 0.0 |
-|     | 1970-01-01T00:06:40 | 0.0 |
-|     | 1970-01-01T00:13:20 | 0.0 |
-|     | 1970-01-01T00:20:00 | 0.0 |
-|     | 1970-01-01T00:26:40 | 0.0 |
-|     | 1970-01-01T00:33:20 | 0.0 |
-| a   | 1970-01-01T00:00:00 | 1.0 |
-| a   | 1970-01-01T00:20:00 | 3.0 |
-| b   | 1970-01-01T00:13:20 | 2.0 |
-| c   | 1970-01-01T00:26:40 | 4.0 |
-+-----+---------------------+-----+
++---------------------+----------------+-----+
+| ts                  | greptime_value | job |
++---------------------+----------------+-----+
+| 1970-01-01T00:00:00 | 0.0            |     |
+| 1970-01-01T00:00:00 | 1.0            | a   |
+| 1970-01-01T00:06:40 | 0.0            |     |
+| 1970-01-01T00:13:20 | 0.0            |     |
+| 1970-01-01T00:13:20 | 2.0            | b   |
+| 1970-01-01T00:20:00 | 0.0            |     |
+| 1970-01-01T00:20:00 | 3.0            | a   |
+| 1970-01-01T00:26:40 | 0.0            |     |
+| 1970-01-01T00:26:40 | 4.0            | c   |
+| 1970-01-01T00:33:20 | 0.0            |     |
++---------------------+----------------+-----+
 
 -- SQLNESS SORT_RESULT 3 1
 tql eval (0, 2000, '400') t2 or on () t1;
 
-+-----+---------------------+-----+
-| job | ts                  | val |
-+-----+---------------------+-----+
-|     | 1970-01-01T00:00:00 | 0.0 |
-|     | 1970-01-01T00:06:40 | 0.0 |
-|     | 1970-01-01T00:13:20 | 0.0 |
-|     | 1970-01-01T00:20:00 | 0.0 |
-|     | 1970-01-01T00:26:40 | 0.0 |
-|     | 1970-01-01T00:33:20 | 0.0 |
-+-----+---------------------+-----+
++---------------------+----------------+-----+
+| ts                  | greptime_value | job |
++---------------------+----------------+-----+
+| 1970-01-01T00:00:00 | 0.0            |     |
+| 1970-01-01T00:06:40 | 0.0            |     |
+| 1970-01-01T00:13:20 | 0.0            |     |
+| 1970-01-01T00:20:00 | 0.0            |     |
+| 1970-01-01T00:26:40 | 0.0            |     |
+| 1970-01-01T00:33:20 | 0.0            |     |
++---------------------+----------------+-----+
 
 -- SQLNESS SORT_RESULT 3 1
 tql eval (0, 2000, '400') t2 or on(job) t1;
 
-+-----+---------------------+-----+
-| job | ts                  | val |
-+-----+---------------------+-----+
-|     | 1970-01-01T00:00:00 | 0.0 |
-|     | 1970-01-01T00:06:40 | 0.0 |
-|     | 1970-01-01T00:13:20 | 0.0 |
-|     | 1970-01-01T00:20:00 | 0.0 |
-|     | 1970-01-01T00:26:40 | 0.0 |
-|     | 1970-01-01T00:33:20 | 0.0 |
-| a   | 1970-01-01T00:00:00 | 1.0 |
-| a   | 1970-01-01T00:20:00 | 3.0 |
-| b   | 1970-01-01T00:13:20 | 2.0 |
-| c   | 1970-01-01T00:26:40 | 4.0 |
-+-----+---------------------+-----+
++---------------------+----------------+-----+
+| ts                  | greptime_value | job |
++---------------------+----------------+-----+
+| 1970-01-01T00:00:00 | 0.0            |     |
+| 1970-01-01T00:00:00 | 1.0            | a   |
+| 1970-01-01T00:06:40 | 0.0            |     |
+| 1970-01-01T00:13:20 | 0.0            |     |
+| 1970-01-01T00:13:20 | 2.0            | b   |
+| 1970-01-01T00:20:00 | 0.0            |     |
+| 1970-01-01T00:20:00 | 3.0            | a   |
+| 1970-01-01T00:26:40 | 0.0            |     |
+| 1970-01-01T00:26:40 | 4.0            | c   |
+| 1970-01-01T00:33:20 | 0.0            |     |
++---------------------+----------------+-----+
 
 drop table t1;
 
diff --git a/tests/cases/standalone/common/promql/set_operation.sql b/tests/cases/standalone/common/promql/set_operation.sql
index 6a71711bd896..521791a02c4f 100644
--- a/tests/cases/standalone/common/promql/set_operation.sql
+++ b/tests/cases/standalone/common/promql/set_operation.sql
@@ -7,7 +7,7 @@ create table http_requests (
     job string,
     instance string,
     g string, -- for `group`
-    val double,
+    greptime_value double,
     primary key (job, instance, g)
 );
 
@@ -27,7 +27,7 @@ create table cpu_count(ts timestamp time index);
 create table vector_matching_a(
     ts timestamp time index,
     l string primary key,
-    val double,
+    greptime_value double,
 );
 
 insert into vector_matching_a values
@@ -176,11 +176,11 @@ drop table vector_matching_a;
 
 -- the following cases are not from Prometheus.
 
-create table t1 (ts timestamp time index, job string primary key, val double);
+create table t1 (ts timestamp time index, job string primary key, greptime_value double);
 
 insert into t1 values (0, "a", 1.0), (500000, "b", 2.0), (1000000, "a", 3.0), (1500000, "c", 4.0);
 
-create table t2 (ts timestamp time index, val double);
+create table t2 (ts timestamp time index, greptime_value double);
 
 insert into t2 values (0, 0), (300000, 0), (600000, 0), (900000, 0), (1200000, 0), (1500000, 0), (1800000, 0);