SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'cca3398862d57a4f66e45a1ded91292f23b73b7033a93b2f6b59217b47801169' 
  AND token = '+6Z6/LojMo5ZoVm0uTQdyGnyhrnYjt3OX9wOxTd7gTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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