materialize the query only once

Author: shizy818

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/relational/planner/CteMaterializer.java

@@ -82,9 +82,10 @@ public void materializeCTE(Analysis analysis, MPPQueryContext context) {
             (tableRef, query) -> {
               Table table = tableRef.getNode();
               if (query.isMaterialized()) {
-                if (!query.isDone()) {
+                if (!query.isExecuted()) {
                   CteDataStore dataStore =
                       fetchCteQueryResult(context, table, query, analysis.getWith());
+                  query.setExecuted(true);
                   if (dataStore == null) {
                     // CTE query execution failed. Use inline instead of materialization
                     // in the outer query

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/relational/sql/ast/Query.java

@@ -44,6 +44,9 @@ public class Query extends Statement {
   private final Optional<Node> limit;
   // whether this query needs materialization
   private boolean materialized = false;
+  // whether this query has ever been executed
+  private boolean isExecuted = false;
+  // materialization has been executed successfully if cteDataStore is not null
   private CteDataStore cteDataStore = null;
 
   public Query(
@@ -115,6 +118,14 @@ public void setMaterialized(boolean materialized) {
     this.materialized = materialized;
   }
 
+  public boolean isExecuted() {
+    return isExecuted;
+  }
+
+  public void setExecuted(boolean executed) {
+    isExecuted = executed;
+  }
+
   public boolean isDone() {
     return cteDataStore != null;
   }