SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c9fb9f16096fbd971dba46cefad045355f420743e32d225f9353d926c86595f5' 
  AND token = 'Hf05G0WhGM9G0eV7SVYqe5+zQVHRIyENmW37wacB+Ms=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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