SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cc084e66797da25a1cfee77a680cec606e262cf139d0077ff3f62fc4fcaec31' 
  AND token = 'xBzFOjZSGjTJ4KeW6UTNDJFyBLEkeOxt2v2cCscFTgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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