SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ced819dcad9891ddfa833d600260ea1e08e0231daa9c119cb4b2bc774ead3a9f' 
  AND token = 'uMA2d1VkHvZb4uir7GuFY+JJeLpYlVuXNuzdiOfu99c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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