chore: minor refactor for extract_scan_fields_from_projection()

Author: drmingdrmer

src/query/service/src/sql/executor/physical_plan_builder.rs

@@ -126,7 +126,7 @@ impl PhysicalPlanBuilder {
                     }
                     if let Some(prewhere) = &scan.prewhere {
                         // if there is a prewhere optimization,
-                        // we can prune `PhysicalScan`'s ouput schema.
+                        // we can prune `PhysicalScan`'s output schema.
                         if prewhere.output_columns.contains(index) {
                             name_mapping.insert(column.name().to_string(), index.to_string());
                         }

src/query/service/src/storages/storage_table_read_plan.rs

@@ -16,12 +16,12 @@ use std::collections::BTreeMap;
 use std::sync::Arc;
 
 use common_datavalues::DataField;
+use common_datavalues::DataSchema;
 use common_exception::Result;
 use common_legacy_planners::Extras;
 use common_legacy_planners::Projection;
 use common_legacy_planners::ReadDataSourcePlan;
 use common_legacy_planners::SourceInfo;
-use common_meta_app::schema::TableInfo;
 
 use crate::sessions::QueryContext;
 use crate::storages::Table;
@@ -55,16 +55,21 @@ impl ToReadDataSourcePlan for dyn Table {
         push_downs: Option<Extras>,
     ) -> Result<ReadDataSourcePlan> {
         let (statistics, parts) = self.read_partitions(ctx, push_downs.clone()).await?;
+
         let table_info = self.get_table_info();
+        let table_meta = &table_info.meta;
         let description = statistics.get_description(table_info);
 
         let scan_fields = match (self.benefit_column_prune(), &push_downs) {
             (true, Some(push_downs)) => match &push_downs.prewhere {
-                Some(prewhere) => {
-                    extract_scan_fields_from_projection(table_info, &prewhere.output_columns)
-                }
+                Some(prewhere) => extract_scan_fields_from_projection(
+                    &table_meta.schema,
+                    &prewhere.output_columns,
+                ),
                 _ => match &push_downs.projection {
-                    Some(projection) => extract_scan_fields_from_projection(table_info, projection),
+                    Some(projection) => {
+                        extract_scan_fields_from_projection(&table_meta.schema, projection)
+                    }
                     _ => None,
                 },
             },
@@ -87,15 +92,13 @@ impl ToReadDataSourcePlan for dyn Table {
 }
 
 fn extract_scan_fields_from_projection(
-    table_info: &TableInfo,
+    schema: &DataSchema,
     projection: &Projection,
 ) -> Option<BTreeMap<usize, DataField>> {
     match projection {
         Projection::Columns(ref indices) => {
-            if indices.len() < table_info.schema().fields().len() {
-                let fields = indices
-                    .iter()
-                    .map(|i| table_info.schema().field(*i).clone());
+            if indices.len() < schema.fields().len() {
+                let fields = indices.iter().map(|i| schema.field(*i).clone());
 
                 Some((indices.iter().cloned().zip(fields)).collect::<BTreeMap<_, _>>())
             } else {
@@ -104,7 +107,7 @@ fn extract_scan_fields_from_projection(
         }
         Projection::InnerColumns(ref path_indices) => {
             let column_ids: Vec<usize> = path_indices.keys().cloned().collect();
-            let new_schema = table_info.schema().inner_project(path_indices);
+            let new_schema = schema.inner_project(path_indices);
             Some(
                 (column_ids.iter().cloned().zip(new_schema.fields().clone()))
                     .collect::<BTreeMap<_, _>>(),