SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0603cf67e926ebf688aa80224c34341761106e83451de1266e0c0fe58d2516d' 
  AND token = 'Q2iu3EjgrcgOmANdYVLAlNmB2WlFuGQD6saRT5iF6Ws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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