PHOENIX-3501 Push limit to server for distinct optimization
diff --git a/phoenix-core/src/it/java/org/apache/phoenix/end2end/DistinctPrefixFilterIT.java b/phoenix-core/src/it/java/org/apache/phoenix/end2end/DistinctPrefixFilterIT.java
index 3d88a43..d66857d 100644
--- a/phoenix-core/src/it/java/org/apache/phoenix/end2end/DistinctPrefixFilterIT.java
+++ b/phoenix-core/src/it/java/org/apache/phoenix/end2end/DistinctPrefixFilterIT.java
@@ -145,6 +145,7 @@
testSkipRange("SELECT %s prefix1 FROM "+ testTable + " GROUP BY prefix1 ORDER BY prefix1 DESC", 3);
testSkipRange("SELECT %s DISTINCT prefix1 FROM " + testTable + " ORDER BY prefix1 DESC", 3);
+ testSkipRange("SELECT %s DISTINCT prefix1 FROM " + testTable + " ORDER BY prefix1 DESC LIMIT 2", 2);
}
@Test
diff --git a/phoenix-core/src/main/java/org/apache/phoenix/iterate/BaseResultIterators.java b/phoenix-core/src/main/java/org/apache/phoenix/iterate/BaseResultIterators.java
index 25f3bec..51587f1 100644
--- a/phoenix-core/src/main/java/org/apache/phoenix/iterate/BaseResultIterators.java
+++ b/phoenix-core/src/main/java/org/apache/phoenix/iterate/BaseResultIterators.java
@@ -232,11 +232,14 @@
!plan.getStatement().getHint().hasHint(HintNode.Hint.RANGE_SCAN) &&
cols < plan.getTableRef().getTable().getRowKeySchema().getFieldCount() &&
plan.getGroupBy().isOrderPreserving() &&
- (context.getAggregationManager().isEmpty() || plan.getGroupBy().isUngroupedAggregate()))
- {
- ScanUtil.andFilterAtEnd(context.getScan(),
+ (context.getAggregationManager().isEmpty() || plan.getGroupBy().isUngroupedAggregate())) {
+
+ ScanUtil.andFilterAtEnd(scan,
new DistinctPrefixFilter(plan.getTableRef().getTable().getRowKeySchema(),
cols));
+ if (plan.getLimit() != null) { // We can push the limit to the server
+ ScanUtil.andFilterAtEnd(scan, new PageFilter(plan.getLimit()));
+ }
}
if (optimizeProjection) {
