Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2ff18846f1474dfffda8bb6e3a6189cecf8e8376134d0e33649a0f20b8fa7f5e' 
  AND token = 'tHE6euJlLGWbLyPVPRiCg7asm9mHM7CC/p/5mCuTIqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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