SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0228a1b6ce20768150864da225a64c68ca527e94aead86f7107a08db58f0beec' 
  AND token = 'Y0pFG4lhtHt0YPOWSUVOs/RLdfs/3B0xU0mYBidHlAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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