fix for 'rollupJoin' pre-aggs

Author: KSDaemon

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

@@ -783,7 +783,7 @@ export class BaseQuery {
   externalPreAggregationQuery() {
     if (!this.options.preAggregationQuery && !this.options.disableExternalPreAggregations && this.externalQueryClass) {
       const preAggregationForQuery = this.preAggregations.findPreAggregationForQuery();
-      if (preAggregationForQuery && preAggregationForQuery.preAggregation.external) {
+      if (preAggregationForQuery?.preAggregation.external) {
         return true;
       }
       const preAggregationsDescription = this.preAggregations.preAggregationsDescription();

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

@@ -1070,7 +1070,8 @@ export class PreAggregations {
       preAggregationName,
       preAggregation,
       cube,
-      canUsePreAggregation: canUsePreAggregation(references) && this.doesQueryAndPreAggJoinTreeMatch(references),
+      // There are no connections in the joinTree between cubes from different datasources for 'rollupJoin' pre-aggs
+      canUsePreAggregation: canUsePreAggregation(references) && (preAggregation.type === 'rollupJoin' || this.doesQueryAndPreAggJoinTreeMatch(references)),
       references,
       preAggregationId: `${cube}.${preAggregationName}`
     };