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SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '8b5c99a62ef882e2e182afacf9bdb94dc28fb860146dd0848b6c250b4781e258' 
  AND token = 'vMMutgraWVQP0bgvoThlZs02YFCkvg+ZjhHmc91t6Is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00949

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}