SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f841c1bb3530f083dabc90a1614b47a7a485fe5e93ec4082c27199c4256693de' 
  AND token = 'X0VxgKMkBnn3Xcxxx2ouQFj8ADZq7+n2+vo0GN8rhX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}