Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4be3aef67f1e364828d679d2dbca06fcbffac55a0de85629cb85572a977e0174' 
  AND token = '79sY0REiSaoE4de1CSevMfcoLy9V9AbDYVBp7JbMwEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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