SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68b8c62763646919da7b8ff2b808df8af85d0277eef582acb53efb459c23ea6c' 
  AND token = 'aOIzzkAEIQiPvOCAXgmwD5Ti5EIx2QiczUuDnS66zOE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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