A side-effect of cursors is stale data. Stale data occurs when records have been changed in a table, but the corresponding records in client buffers have not been updated to reflect the changes. The following scenario illustrates how stale data occurs.
You won’t be able to eliminate stale data, but you can reduce the chances of it occurring. One solution is to reduce the cursor block size. By storing fewer records in the client buffer, you will reduce the number that could become stale. You can also use cursor refreshing, described in the next section, to help reduce the occurrence of stale data.