SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '845f19320f776aec90d5f04dfd26d1c88766e1dfba324d567943eafb4eafd0ce' 
  AND token = 'LiaZQ/ESN7NmB0EShb0vbDQvsK9g6DqoLBqZ01LpxaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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