Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68cca8558075c29b59916c5f59afd1be9f62b93e44fe8da93c20818093ffba2e' 
  AND token = '7L2xKSlyYs303swrL683s2Cop/cbe2tKBFsXB4TJ384=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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