I have a reason to use WordPress as a front end and Google Spreadsheet as a backend. I have been looking high and low for a plugin which would allow me to pull content from the spreadsheet and then edit it in the WordPress interface, save it back to the Google Spreadsheet. The advantage to this would be that as record in my spreadsheet would go into a single row, that I could then spice up the UI a bit to make things logical for users. – No luck.

• Inline Google Docs http://wordpress.org/extend/plugins/inline-google-docs/

  Many people maintain dynamic content on Google Documents or hold volatile data on Google Spreadsheets. These change when collaborators save an update or users submit a form. Occasionally, one may wish to embed the contents of one’s Google Documents or Spreadsheets in a post or page to reflect the latest updates on one’s blog. This plugin seeks to provide this functionality without using an <iframe>. In addition, it caches contents of the Google Documents or Spreadsheets to speed up page loading.

• Google Docs Viewer http://wordpress.org/extend/plugins/google-docs-viewer/
  This plugin provides multiple viewing functions related to Google Docs.

  First of all it can allow you to easily convert a link to a document so that it uses Google Docs as the viewer. Secondly, it provides a method of embedding certain document types directly into your post or page.

• Inline Google Spreadsheet Viewer http://wordpress.org/extend/plugins/inline-google-spreadsheet-viewer/

  Fetches a published Google Spreadsheet using a [gdoc key=""] WordPress shortcode, then renders it as an HTML table, embedded in your blog post or page. The only required parameter is key, which specifies the document you’d like to retrieve. Optionally, you can also strip a certain number of rows (e.g., strip=”3″ omits the top 3 rows of the spreadsheet) and you can supply a table summary,

  and customized class value.
• Google Doc Embedder http://wordpress.org/extend/plugins/google-document-embedder/
  Google Doc Embedder lets you embed several types of files into your WordPress pages using the Google Docs Viewer – allowing inline viewing (and optional downloading) of the following file types, with no Flash or PDF browser plug-ins required.

None of these things did what I really wanted. So, I kept looking. Eventually I found this Publishing Google docs to your blog, which talks about taking a GoogleDocs Writer document and letting it be the data for your post. But I wanted Spread sheet stuff.

Then I found HOW TO: USE GOOGLE SPREADSHEETS AS A DATA SOURCE IN WORDPRESS from 2008 (part 2). That is like a century ago. I am not sure there were even WP Custom Posts around then. But this source only tells one how to get data out of Google Spread Sheets (and I think that Google Spread Sheets have updated since then too).

There was one hopeful solution. That is PhpGrid and the phpGrid Lite WordPress Plugin (on Extend). I think I could take my whole data model and apply it inside of PhpGrid and not need Google Spread sheet.

phpGrid Lite WordPress Plugin is based on phpGrid Lite, a free version of phpGrid. phpGrid is a simple and fully customizable PHP control for generating data-bound, AJAX, PHP datagrid.

Grid-based editing, create, read, update and delete (CRUD), are the most common operations for web developers. With phpGrid web-based data editing is easy. Even with little programming background, one can develop professional looking, AJAX-enabled PHP datagrids in just a few minutes.

Finally, I did find out about GoogleDoc’s Data APIby reading Saving Form Data to Google Spreadsheets Using PHP and the Google Docs API by far IN space WEB+, but I just want to plug something in and it to work. So this solution got pushed no further. (And they were using an older, depreciated version of the API).