From 6b8475313b0155020218c15f4acf1572d111458e Mon Sep 17 00:00:00 2001
From: Teodor Sigaev <teodor@sigaev.ru>
Date: Tue, 11 Apr 2017 15:16:50 +0300
Subject: [PATCH] improve support for fasttruncate

---
 online_analyze.c | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/online_analyze.c b/online_analyze.c
index 2ef4193..22c43e6 100644
--- a/online_analyze.c
+++ b/online_analyze.c
@@ -82,9 +82,11 @@ typedef enum CmdKind
 	CK_INSERT = CMD_INSERT,
 	CK_DELETE = CMD_DELETE,
 	CK_TRUNCATE,
+	CK_FASTTRUNCATE,
 	CK_CREATE
 } CmdKind;
 
+
 typedef enum
 {
 	OATT_ALL		= 0x03,
@@ -368,6 +370,9 @@ makeAnalyze(Oid relOid, CmdKind operation, int64 naffected)
 	if (relOid == InvalidOid)
 		return;
 
+	elog(NOTICE,"makeAnalyze operation: %d	naffected: %d",
+		 operation, (int32)naffected);
+
 	if (naffected == 0)
 		/* return if there is no changes */
 		return;
@@ -443,12 +448,10 @@ makeAnalyze(Oid relOid, CmdKind operation, int64 naffected)
 
 	Assert(rstat->tableid == relOid);
 
-	elog(NOTICE,"makeAnalyze op:%d %u", operation, naffected);
-
-	if (operation != CK_TRUNCATE &&
-		(found == false || rstat->rereadStat == true))
+	/* do not rered data if it was a truncation */
+	if (operation != CK_TRUNCATE && operation != CK_FASTTRUNCATE &&
+		(newTable == true || rstat->rereadStat == true))
 	{
-
 		rstat->rereadStat = false;
 
 		tabentry = pgstat_fetch_stat_tabentry(relOid);
@@ -470,7 +473,7 @@ makeAnalyze(Oid relOid, CmdKind operation, int64 naffected)
 	}
 
 	if (newTable ||
-		/* force analyze from after truncate */
+		/* force analyze after truncate, fasttruncate already did analyze */
 		operation == CK_TRUNCATE || (
 		/* do not analyze too often, if both stamps are exceeded the go */
 		TimestampDifferenceExceeds(rstat->analyze_timestamp, now, online_analyze_min_interval) &&
@@ -553,20 +556,16 @@ makeAnalyze(Oid relOid, CmdKind operation, int64 naffected)
 
 		switch(operation)
 		{
+			case CK_CREATE:
 			case CK_INSERT:
-				rstat->n_tuples += naffected;
-				rstat->rereadStat = false;
-				break;
 			case CK_UPDATE:
 				rstat->n_tuples += naffected;
-				rstat->rereadStat = true;
-				break;
 			case CK_DELETE:
-				rstat->rereadStat = true;
+				rstat->rereadStat = (reltype == OATT_PERSISTENT);
 				break;
 			case CK_TRUNCATE:
+			case CK_FASTTRUNCATE:
 				rstat->n_tuples = 0;
-				rstat->rereadStat = false;
 				break;
 			default:
 				break;
@@ -592,6 +591,7 @@ makeAnalyze(Oid relOid, CmdKind operation, int64 naffected)
 #endif
 		switch(operation)
 		{
+			case CK_CREATE:
 			case CK_INSERT:
 				rstat->changes_since_analyze += naffected;
 				rstat->n_tuples += naffected;
@@ -603,6 +603,7 @@ makeAnalyze(Oid relOid, CmdKind operation, int64 naffected)
 				rstat->changes_since_analyze += naffected;
 				break;
 			case CK_TRUNCATE:
+			case CK_FASTTRUNCATE:
 				rstat->changes_since_analyze = 0;
 				rstat->n_tuples = 0;
 				break;
@@ -675,6 +676,7 @@ onlineAnalyzeHooker(QueryDesc *queryDesc)
 	if (queryDesc->estate)
 		naffected = queryDesc->estate->es_processed;
 
+#if PG_VERSION_NUM >= 90200
 	if (online_analyze_enable &&
 		(constval = isFastTruncateCall(queryDesc)) != NULL)
 	{
@@ -684,12 +686,11 @@ onlineAnalyzeHooker(QueryDesc *queryDesc)
 			makeRangeVarFromNameList(stringToQualifiedNameList(tblname));
 
 		makeAnalyze(RangeVarGetRelid(tblvar,
-#if PG_VERSION_NUM >= 90200
 									 NoLock,
-#endif
 									 false),
-					CK_TRUNCATE, -1);
+					CK_FASTTRUNCATE, -1);
 	}
+#endif
 
 	if (online_analyze_enable && queryDesc->plannedstmt &&
 			(queryDesc->operation == CMD_INSERT ||
-- 
2.37.3