1 files changed, 1 insertions, 0 deletions
diff --git a/doc/TODO b/doc/TODO
index 0930c695f01..1e6fdaef0d6 100644
--- a/doc/TODO
+++ b/doc/TODO
@@ -48,6 +48,7 @@ PARSER
 * redesign INSERT ... SELECT to have two levels of target list
 * -select * from pg_class where oid in (0,-1)
 * have INTERSECT/EXCEPT prevent duplicates unless ALL is specified
+* prevent primary key of nine columns(see TODO.detail/primary)
 
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