SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3242fb3d3e8675b1a4a2251832b29272572d436c99446db18ccc8ecd07616a2' 
  AND token = 'm23eUuU5q1bHohrLlCcz0/hFIqd1N29ZxUlqa0MpljQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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