diff --git a/dbms/src/Parsers/ParserTablesInSelectQuery.cpp b/dbms/src/Parsers/ParserTablesInSelectQuery.cpp
index 16e1bdec302..4c300221db8 100644
--- a/dbms/src/Parsers/ParserTablesInSelectQuery.cpp
+++ b/dbms/src/Parsers/ParserTablesInSelectQuery.cpp
@@ -149,6 +149,7 @@ bool ParserTablesInSelectQueryElement::parseImpl(Pos & pos, ASTPtr & node, Expec
                 table_join->kind = ASTTableJoin::Kind::Cross;
             else
             {
+                /// Use INNER by default as in another DBMS.
                 table_join->kind = ASTTableJoin::Kind::Inner;
             }