From d681bbacfd56db07a145b2981e8a4354f2388740 Mon Sep 17 00:00:00 2001
From: Ivan Kush <ivan.v.kush@yandex.ru>
Date: Fri, 31 Oct 2025 21:20:12 +0300
Subject: [PATCH] Move PushActiveSnapshot outside a for loop (#8253)

In the PR [8142](https://github.com/citusdata/citus/pull/8142) was added
`PushActiveSnapshot`.

This commit places it outside a for loop as taking a snapshot is a resource
heavy operation.
---
 src/backend/columnar/columnar_metadata.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/backend/columnar/columnar_metadata.c b/src/backend/columnar/columnar_metadata.c
index 0b4f2400c..159c126f7 100644
--- a/src/backend/columnar/columnar_metadata.c
+++ b/src/backend/columnar/columnar_metadata.c
@@ -618,7 +618,13 @@ SaveStripeSkipList(RelFileLocator relfilelocator, uint64 stripe,
 	Oid columnarChunkOid = ColumnarChunkRelationId();
 	Relation columnarChunk = table_open(columnarChunkOid, RowExclusiveLock);
 	ModifyState *modifyState = StartModifyRelation(columnarChunk);
+	bool pushed_snapshot = false;
 
+	if (!ActiveSnapshotSet())
+	{
+		PushActiveSnapshot(GetTransactionSnapshot());
+		pushed_snapshot = true;
+	}
 	for (columnIndex = 0; columnIndex < columnCount; columnIndex++)
 	{
 		for (chunkIndex = 0; chunkIndex < chunkList->chunkCount; chunkIndex++)
@@ -659,11 +665,13 @@ SaveStripeSkipList(RelFileLocator relfilelocator, uint64 stripe,
 				nulls[Anum_columnar_chunk_minimum_value - 1] = true;
 				nulls[Anum_columnar_chunk_maximum_value - 1] = true;
 			}
-			PushActiveSnapshot(GetTransactionSnapshot());
 			InsertTupleAndEnforceConstraints(modifyState, values, nulls);
-			PopActiveSnapshot();
 		}
 	}
+	if (pushed_snapshot)
+	{
+		PopActiveSnapshot();
+	}
 
 	FinishModifyRelation(modifyState);
 	table_close(columnarChunk, RowExclusiveLock);