SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb0ac375d1c95ba4a8e2edec73d1700701a697355af80a8aeefcc199e4eadea5' 
  AND token = 'O3IQOJbg3weJFITYwEd8OgvaMxxKLwwhwhfg6hcozL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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