Upsert

MERGE article WITH (HOLDLOCK) AS t
USING (SELECT CAST(? AS NVARCHAR(40))  AS code,
              CAST(? AS NVARCHAR(200)) AS title,
              CAST(? AS NVARCHAR(500)) AS summary,
              CAST(? AS NVARCHAR(60))  AS category,
              CAST(? AS NVARCHAR(300)) AS tags,
              CAST(? AS NVARCHAR(10))  AS priority) AS s
   ON t.code = s.code
WHEN MATCHED AND t.locked = 0 THEN
    UPDATE SET t.title = s.title,
               t.summary = s.summary,
               t.category = s.category,
               t.tags = s.tags,
               t.priority = s.priority,
               t.row_version = t.row_version + 1,
               t.updated_at = SYSDATETIME()
WHEN NOT MATCHED THEN
    INSERT (code, title, summary, category, tags, priority, status, is_read, read_at)
    VALUES (s.code, s.title, s.summary, s.category, s.tags, s.priority, N'DRAFT', 1, SYSDATETIME())
OUTPUT $action AS merge_action, inserted.id AS id;

• WITH (HOLDLOCK) keeps the key range locked until the end, so two users cannot both INSERT the same code.
• WHEN MATCHED AND t.locked = 0: a locked row matches but no branch runs, so nothing is returned.
• OUTPUT $action returns INSERT or UPDATE, which the page shows above.
• CAST(? AS NVARCHAR(..)) gives each parameter a clear type for the comparison.