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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f8ce4919a8c0dbd5002e0474e8f9d1fb553361a997890f8c42e345bd4bd9b95c' 
  AND token = 'okdpGsfpzMpn0fRQyYTFKn5Lc2yolDtXq4xns1OU/EY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}