The Firefox add-on mechanism has been used to develop a number of FTP clients and file browsers, which effectively replicate some of the features of the operating system, albeit on a more restricted platform.
In the database world, developers are sometimes tempted to bypass the RDBMS, for example by storing everything in one big table with three columns labelled entity ID, key, and value.
While this entity-attribute-value model enables the developer to break out from the structure imposed by an SQL database, it loses out on all the benefits,[1] since all of the work that could be done efficiently by the RDBMS is forced onto the application instead.
A similar temptation exists for XML, where developers sometimes favor generic element names and use attributes to store meaningful information.
[citation needed] On the other hand, such functions are often created to present a simpler (and often more portable) abstraction layer on top of lower level services that either have an awkward interface, are too complex, non-portable or insufficiently portable, or simply a poor match for higher level application code.