0001-EXPLAIN-JSON-format-should-not-add-quotes-in-index-n.patch

From 5441915ddb26af9b7d861c988b6d99757130424e Mon Sep 17 00:00:00 2001
From: Euler Taveira <euler.taveira@2ndquadrant.com>
Date: Sat, 20 Jun 2020 14:14:49 -0300
Subject: [PATCH] EXPLAIN JSON format should not add quotes in index names

JSON format does not have to quote relation names. However, index names
are quoted twice. It was reported in bug #16502.
---
 src/backend/commands/explain.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 67bdcb2b27..250af77a1a 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -115,7 +115,7 @@ static void show_instrumentation_count(const char *qlabel, int which,
 									   PlanState *planstate, ExplainState *es);
 static void show_foreignscan_info(ForeignScanState *fsstate, ExplainState *es);
 static void show_eval_params(Bitmapset *bms_params, ExplainState *es);
-static const char *explain_get_index_name(Oid indexId);
+static const char *explain_get_index_name(Oid indexId, ExplainState *es);
 static void show_buffer_usage(ExplainState *es, const BufferUsage *usage);
 static void show_wal_usage(ExplainState *es, const WalUsage *usage);
 static void ExplainIndexScanDetails(Oid indexid, ScanDirection indexorderdir,
@@ -1453,7 +1453,7 @@ ExplainNode(PlanState *planstate, List *ancestors,
 			{
 				BitmapIndexScan *bitmapindexscan = (BitmapIndexScan *) plan;
 				const char *indexname =
-				explain_get_index_name(bitmapindexscan->indexid);
+				explain_get_index_name(bitmapindexscan->indexid, es);
 
 				if (es->format == EXPLAIN_FORMAT_TEXT)
 					appendStringInfo(es->str, " on %s", indexname);
@@ -3269,7 +3269,7 @@ show_eval_params(Bitmapset *bms_params, ExplainState *es)
  * indexes can be explained.
  */
 static const char *
-explain_get_index_name(Oid indexId)
+explain_get_index_name(Oid indexId, ExplainState *es)
 {
 	const char *result;
 
@@ -3283,7 +3283,9 @@ explain_get_index_name(Oid indexId)
 		result = get_rel_name(indexId);
 		if (result == NULL)
 			elog(ERROR, "cache lookup failed for index %u", indexId);
-		result = quote_identifier(result);
+		/* don't quote all formats, some formats have its own quote routine */
+		if (es->format == EXPLAIN_FORMAT_TEXT)
+			result = quote_identifier(result);
 	}
 	return result;
 }
@@ -3457,7 +3459,7 @@ static void
 ExplainIndexScanDetails(Oid indexid, ScanDirection indexorderdir,
 						ExplainState *es)
 {
-	const char *indexname = explain_get_index_name(indexid);
+	const char *indexname = explain_get_index_name(indexid, es);
 
 	if (es->format == EXPLAIN_FORMAT_TEXT)
 	{
-- 
2.20.1