Embedded objects

As with word processing software, many database and spreadsheet applications allow users to embed other media (especially images) within files. Whereas databases are more likely to store links to external files rather than the files themselves, spreadsheet applications such as Microsoft Excel and OpenOffice Calc allow users to embed graphs and charts generated from data along with other images. Again, as with text files, it is advisable that such content is stored and archived separately thereby retaining the original qualities of the content (e.g. image resolution) and allowing it to follow a separate archival strategy to the textual content.

Data consistency and documentation

Coded or inconsistently entered data presents a problem for both databases and spreadsheets when it comes to data reuse. Coded fields and data should be adequately documented and such documentation should be archived alongside the database or spreadsheet so that the meaning of fields or data is not lost over time. Inconsistent data entry (which can be controlled to a greater extent within databases than spreadsheets) can also result in the meaning of data being lost (e.g. is ‘A’ actually equal to ‘a’?) and provide problems with querying the dataset.

Non-data content

As discussed above (and in more detail later on) both databases and spreadsheets can consist of more than just tabular data, charts and images. Spreadsheet applications in particular allow a great deal of formatting (i.e. font colour and style, cell colour, border styles) to be applied to data and the cells that contain it. In general, such styles are usually employed to highlight certain aspects of the data (such as column totals, negative figures and so on) but often these styles can be used to convey meaning which can then be lost during data migrations (especially to plain text).