SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7972b8c6961eb9c8cf1987fcc218f84d683d24948b3b7c367711595e5edeb884' 
  AND token = 'VNvA9UOiwE4ojgiBt/5GdKPPvtuZ4dIo8tcs4anE6AY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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