SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1942de34d84ff8a5bfbf2b2462716c8841c35400f3081236a757d5dd2ebb5965' 
  AND token = 'VhStotssB98DPXfNEX4yGrJ0+ZZuP7u12O/yl5CnWRY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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