diff --git a/src/backend/utils/adt/rangetypes.c b/src/backend/utils/adt/rangetypes.c
index c2f0b2559b..fe9e0c4bc6 100644
--- a/src/backend/utils/adt/rangetypes.c
+++ b/src/backend/utils/adt/rangetypes.c
@@ -1902,7 +1902,7 @@ range_parse_flags(const char *flags_str)
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
 					 errmsg("invalid range bound flags"),
-				   errhint("Valid values are '[]', '[)', '(]', and '()'.")));
+				 errhint("Valid values are \"[]\", \"[)\", \"(]\", and \"()\".")));
 	}
 
 	switch (flags_str[1])
@@ -1916,7 +1916,7 @@ range_parse_flags(const char *flags_str)
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
 					 errmsg("invalid range bound flags"),
-				   errhint("Valid values are '[]', '[)', '(]', and '()'.")));
+				 errhint("Valid values are \"[]\", \"[)\", \"(]\", and \"()\".")));
 	}
 
 	return flags;