From ad2052e8e52b2ee33f0d214b0800c64dc2b60c7f Mon Sep 17 00:00:00 2001
From: Maksim Kita <kitaetoya@gmail.com>
Date: Tue, 21 Sep 2021 02:23:34 +0300
Subject: [PATCH] Added comments

---
 src/Parsers/ASTSystemQuery.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Parsers/ASTSystemQuery.cpp b/src/Parsers/ASTSystemQuery.cpp
index f50bcf5041f..ba8e49b98ca 100644
--- a/src/Parsers/ASTSystemQuery.cpp
+++ b/src/Parsers/ASTSystemQuery.cpp
@@ -31,6 +31,9 @@ namespace
 
 const char * ASTSystemQuery::typeToString(Type type)
 {
+    /** During parsing if SystemQuery is not parsed properly it is added to Expected variants as description check IParser.h.
+      * Description string must be statically allocated.
+      */
     static std::vector<std::string> type_index_to_type_name = getTypeIndexToTypeName();
     const auto & type_name = type_index_to_type_name[static_cast<UInt64>(type)];
     return type_name.data();