Rename column slotsync_skip_at to slotsync_last_skip.

Commit 76b78721ca introduced two new columns in pg_stat_replication_slots
to improve monitoring of slot synchronization. One of these columns was
named slotsync_skip_at, which is inconsistent with the naming convention
used for similar columns in other system views.

Columns that store timestamps of the most recent event typically use the
'last_' in the column name (e.g., last_autovacuum, checksum_last_failure).
Renaming slotsync_skip_at to slotsync_last_skip aligns with this pattern,
making the purpose of the column clearer and improving overall consistency
across the views.

Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: Michael Banck <mbanck@gmx.net>
Discussion: https://postgr.es/m/20251128091552.GB13635@p46.dedyn.io;lightning.p46.dedyn.io
Discussion: https://postgr.es/m/CAE9k0PkhfKrTEAsGz4DjOhEj1nQ+hbQVfvWUxNacD38ibW3a1g@mail.gmail.com

7 files changed, 10 insertions, 10 deletions

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 086c4c8fb6f..48af8ee90a6 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -1078,7 +1078,7 @@ CREATE VIEW pg_stat_replication_slots AS
             s.total_txns,
             s.total_bytes,
             s.slotsync_skip_count,
-            s.slotsync_skip_at,
+            s.slotsync_last_skip,
             s.stats_reset
     FROM pg_replication_slots as r,
         LATERAL pg_stat_get_replication_slot(slot_name) as s
diff --git a/src/backend/utils/activity/pgstat_replslot.c b/src/backend/utils/activity/pgstat_replslot.c
index e08d33e8b4c..d757e00eb54 100644
--- a/src/backend/utils/activity/pgstat_replslot.c
+++ b/src/backend/utils/activity/pgstat_replslot.c
@@ -127,7 +127,7 @@ pgstat_report_replslotsync(ReplicationSlot *slot)
 	statent = &shstatent->stats;
 
 	statent->slotsync_skip_count += 1;
-	statent->slotsync_skip_at = GetCurrentTimestamp();
+	statent->slotsync_last_skip = GetCurrentTimestamp();
 
 	pgstat_unlock_entry(entry_ref);
 }
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 7e2ed69138a..ef6fffe60b9 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -2162,7 +2162,7 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 					   INT8OID, -1, 0);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 11, "slotsync_skip_count",
 					   INT8OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 12, "slotsync_skip_at",
+	TupleDescInitEntry(tupdesc, (AttrNumber) 12, "slotsync_last_skip",
 					   TIMESTAMPTZOID, -1, 0);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 13, "stats_reset",
 					   TIMESTAMPTZOID, -1, 0);
@@ -2192,10 +2192,10 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 	values[9] = Int64GetDatum(slotent->total_bytes);
 	values[10] = Int64GetDatum(slotent->slotsync_skip_count);
 
-	if (slotent->slotsync_skip_at == 0)
+	if (slotent->slotsync_last_skip == 0)
 		nulls[11] = true;
 	else
-		values[11] = TimestampTzGetDatum(slotent->slotsync_skip_at);
+		values[11] = TimestampTzGetDatum(slotent->slotsync_last_skip);
 
 	if (slotent->stat_reset_timestamp == 0)
 		nulls[12] = true;
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 70320aa0cfb..d13ed62af46 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202511281
+#define CATALOG_VERSION_NO	202512051
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 66af2d96d67..fd9448ec7b9 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5693,7 +5693,7 @@
   proparallel => 'r', prorettype => 'record', proargtypes => 'text',
   proallargtypes => '{text,text,int8,int8,int8,int8,int8,int8,int8,int8,int8,int8,timestamptz,timestamptz}',
   proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{slot_name,slot_name,spill_txns,spill_count,spill_bytes,stream_txns,stream_count,stream_bytes,mem_exceeded_count,total_txns,total_bytes,slotsync_skip_count,slotsync_skip_at,stats_reset}',
+  proargnames => '{slot_name,slot_name,spill_txns,spill_count,spill_bytes,stream_txns,stream_count,stream_bytes,mem_exceeded_count,total_txns,total_bytes,slotsync_skip_count,slotsync_last_skip,stats_reset}',
   prosrc => 'pg_stat_get_replication_slot' },
 
 { oid => '6230', descr => 'statistics: check if a stats object exists',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index ad85134f27a..f23dd5870da 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -401,7 +401,7 @@ typedef struct PgStat_StatReplSlotEntry
 	PgStat_Counter total_txns;
 	PgStat_Counter total_bytes;
 	PgStat_Counter slotsync_skip_count;
-	TimestampTz slotsync_skip_at;
+	TimestampTz slotsync_last_skip;
 	TimestampTz stat_reset_timestamp;
 } PgStat_StatReplSlotEntry;
 
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 94e45dd4d57..85d795dbd63 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2153,10 +2153,10 @@ pg_stat_replication_slots| SELECT s.slot_name,
     s.total_txns,
     s.total_bytes,
     s.slotsync_skip_count,
-    s.slotsync_skip_at,
+    s.slotsync_last_skip,
     s.stats_reset
    FROM pg_replication_slots r,
-    LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, mem_exceeded_count, total_txns, total_bytes, slotsync_skip_count, slotsync_skip_at, stats_reset)
+    LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, mem_exceeded_count, total_txns, total_bytes, slotsync_skip_count, slotsync_last_skip, stats_reset)
   WHERE (r.datoid IS NOT NULL);
 pg_stat_slru| SELECT name,
     blks_zeroed,