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Author: KSDaemon

packages/cubejs-schema-compiler/src/adapter/BaseQuery.js

@@ -4747,6 +4747,11 @@ export class BaseQuery {
     };
   }
 
+  /**
+   * Returns a function that constructs the full member path
+   * based on the query's join structure.
+   * @returns {(function(member: string): (string))}
+   */
   resolveFullMemberPathFn() {
     const { root: queryJoinRoot } = this.join || {};
 

packages/cubejs-schema-compiler/src/adapter/PreAggregations.ts

@@ -1276,6 +1276,12 @@ export class PreAggregations {
         const aggregateMeasures = preAggQuery?.fullKeyQueryAggregateMeasures({ hasMultipliedForPreAggregation: true });
         references.multipliedMeasures = aggregateMeasures?.multipliedMeasures?.map(m => m.measure);
         if (preAggQuery) {
+          // We need to build a join tree for all references, so they would always include full join path
+          // even for preaggregation references without join path. It is necessary to be able to match
+          // query and preaggregation based on full join tree. But we can not update
+          // references.{dimensions,measures,timeDimensions} directly, because it will break
+          // evaluation of references in the query on later stages.
+          // So we store full named members separately and use them in canUsePreAggregation functions.
           references.joinTree = preAggQuery.join;
           const root = references.joinTree?.root || '';
           references.fullNameMeasures = references.measures.map(m => (m.startsWith(root) ? m : `${root}.${m}`));