Thursday 30 November 2017

What shall I do for International Digital Preservation Day?

I have been thinking about this question for a few months now and have only recently come up with a solution.

I wanted to do something big on International Digital Preservation Day. Unfortunately other priorities have limited the amount of time available and I am doing something a bit more low key. To take a positive from a negative I would like to suggest that as with digital preservation more generally, it is better to just do something rather than wait for the perfect solution to come along!

I am sometimes aware that I spend a lot of time in my own echo chamber - for example talking on Twitter and through this blog to other folks who also work in digital preservation. Though this is undoubtedly a useful two-way conversation, for International Digital Preservation Day I wanted to target some new audiences.

So instead of blogging here (yes I know I am blogging here too) I have blogged on the Borthwick Institute for Archives blog.

The audience for the Borthwick blog is a bit different to my usual readership. It is more likely to be read by users of our services at the Borthwick Institute and those who donate or deposit with us, perhaps also by staff working in other archives in the UK and beyond. Perfect for what I had planned.

In response to the tagline of International Digital Preservation Day ‘Bits Decay: Do Something Today’ I wanted to encourage as many people as possible to ‘Do Something’. This shouldn’t be just limited to us digital preservation folks, but to anyone anywhere who uses a computer to create or manage data.

This is why I decided to focus on Personal Digital Archiving. The blog post is called “Save your digital stuff!” (credit to the DPC Technology Watch Report on Personal Digital Archiving for this inspiring title - it was noted that at a briefing day hosted by the Digital Preservation Coalition (DPC) in April 2015, one of the speakers suggested that the term ‘personal digital archiving’ be replaced by the more urgent exhortation, ‘Save your digital stuff!’).

The blog post aimed to highlight the fragility of digital resources and then give a few tips on how to protect them. Nothing too complicated or technical, but hopefully just enough to raise awareness and perhaps encourage engagement. Not wishing to replicate all the great work that has already been done on Personal Digital Archiving, by the Library of Congress, the Paradigm project and others I decided to focus on just a few simple pieces of advice and then link out to other resources.

At the end of the post I encourage people to share information about any actions they have taken to protect their own digital legacies (of course using the #IDPD17 hashtag). If I inspire just one person to take action I'll consider it a win!

I'm also doing a 'Digital Preservation Takeover' of the Borthwick twitter account @UoYBorthwick. I lined up a series of 'fascinating facts' about the digital archives we hold here at the Borthwick and tweeted them over the course of the day.

  • There are 28 archives at the Borthwick for which we hold at least some digital material - this may be some of the most fragile and vulnerable material that we hold
  • The first digital archive received at the Borthwick arrived in 2004 as part of the York Peptic Ulcer Trust archive
  • We hold 135GB of deposited digital archive material here at the Borthwick (10896 individual files to preserve) - not a huge amount but we do expect this to grow!
  • The largest digital archive we hold at the Borthwick is the Historic Masters Archive which consists of 997 files and is 82 GB in size - it came in yesterday and I’m processing it right now!
  • We believe that the oldest files in the digital archive go back to 1984 - these are in the Marks and Gran archive
  • Approximately a quarter of the digital archives that we hold contain file formats that are not automatically identified by DROID
  • The average number of files received in a digital archive deposit at the Borthwick is 300 (though in reality it can range from 1 to 2400)
  • The average number of different file formats (at least those that can be identified)  in a new digital accession received at the Borthwick is 6, though our Richard Orton archive contains 48 different identified file formats and many more that are not identified
  • The file format that gets deposited with us the most is the Microsoft Word Document 97-2003 (we have over 1700 of these)


OK - admittedly they won't be fascinating to everyone, but if nothing else it helps us to move further away from the notion that an archive is where you go to look at very old documents!

...and of course I now have a whole year to plan for International Digital Preservation Day 2018 so perhaps I'll be able to do something bigger and better?! I'm certainly feeling inspired by the range of activities going on across the globe today.



Jenny Mitcham, Digital Archivist

Wednesday 29 November 2017

Preserving Google Drive: What about Google Sheets?

There was lots of interest in a blog post earlier this year about preserving Google Docs.

Often the issues we grapple with in the field of digital preservation are not what you'd call 'solved problems' and that is what makes them so interesting. I always like to hear how others are approaching these same challenges so it is great to see so many comments on the blog itself and via Twitter.

This time I'm turning my focus to the related issue of Google Sheets. This is the native spreadsheet application for Google Drive.

Why?

Again, this is an application that is widely used at the University of York in a variety of different contexts, including for academic research data. We need to think about how we might preserve data created in Google Sheets for the longer term.


How hard can it be?

Quite hard actually - see my earlier post!


Exporting from Google Drive

For Google Sheets I followed a similar methodology to Google Docs. Taking a couple of sample spreadsheets and downloading them in the formats that Google provides, then examining these exported versions to assess how well specific features of the spreadsheet were retained.

I used the File...Download as... menu in Google Sheets to test out the available export formats

The two spreadsheets I worked with were as follows:

  • A simple spreadsheet which staff had used to select their menu choices for a celebration event. This consisted of just one sheet of data and no particularly advanced features. The sheet did include use of the Google Drive comments facility
  • My flexitime sheet which is provided by my department and used to record the hours I work over the course of the year. It seems to be about as complex as it gets and includes a whole range of features: multiple sheets (that reference each other), controlled data entry through drop down lists, calculations of hours using formula, conditional formatting (ie: specific cells turning red if you have left work too early or taken an inadequate lunch break), code that jumps straight to today's date when you first open it up.

Here is a summary of my findings:

Microsoft Excel - xlsx

I had high hopes for the xlsx export option - however, on opening the exported xlsx version of my flexisheet I was immediately faced with an error message telling me that the file contained unreadable content and asking whether I wanted to recover the contents.

This doesn't look encouraging...

Clicking 'Yes' on this dialogue box then allows the sheet to open and another message appears telling you what has been repaired. In this case it tells me that a formula has been removed.


Excel can open the file if it removes the formula

This is not ideal if the formula is considered to be worthy of preservation.

So clearly we already know that this isn't going to be a perfect copy of the Google sheet.

This version of my flexisheet looks pretty messed up. The dates and values look OK, but none of the calculated values are there - they are all replaced with "#VALUE".

The colours on the original flexisheet are important as they flag up problems and issues with the data entered. These however are not fully retained - for example, weekends are largely (but not consistently) marked as red and in the original file they are green (because it is assumed that I am not actually meant to be working weekends).

The XLSX export does however give a better representation of the more simple menu choices Google sheet. The data is accurate, and comments are present in a partial way. Unfortunately though, replies to comments are not displayed and the comments are not associated with a date or time.


Open Document Format - ods

I tried opening the ODS version of the flexisheet in LibreOffice on a Macbook. There were no error messages (which was nice) but the sheet was a bit of a mess. There were similar issues to those that I encountered in the Excel export though it wasn't identical. The colours were certainly applied differently, neither entirely accurate to the original.

If I actually tried to use the sheet to enter more data in, the formula do not work - they do not calculate anything, though it does appear that the formula itself appears to be retained. Any values that are calculated on the original sheet are not present.

Comments are retained (and replies to comments) but no date or time appears to be associated with them (note that the data may be there but just not displaying in LibreOffice).

I also tried opening the ODS file in Microsoft Office. On opening it the same error message was displayed to the one originally encountered in the XLSX version described above and this was followed by notification that “Excel completed file level validation and repair. Some parts of this workbook may have been repaired or discarded.” Unlike the XLSX file there didn't appear to be any additional information available about exactly what had been repaired or discarded - this didn't exactly fill me with confidence!

PDF document - pdf

When downloading a spreadsheet as a PDF you are presented with a few choices - for example:
  • Should the export include all sheets, just the current sheet or current selection (note that current sheet is the default response)
  • Should the export include the document title?
  • Should the export include sheet names?
To make the export as thorough as possible I chose to export all sheets and include document title and sheet names.

As you might expect this was a good representation of the values on the spreadsheet - a digital print if you like - but all functionality and interactivity was lost. In order to re-use the data, it would need to be copied and pasted or re-typed back into a spreadsheet application.

Note that comments within the sheet were not retained and also there was no option to export sheets that were hidden.

Web page - html

This gave an accurate representation of the values on the spreadsheet, but, similar to the PDF version, not in a way that really encourages reuse. Formula were not retained and the resulting copy is just a static snapshot.

Interestingly, the comments in the menu choices example weren't retained. This surprised me because when using the html export option for Google documents one of the noted benefits was that comments were retained. Seems to be a lack of consistency here.

Another thing that surprised me about this version of the flexisheet was that it included hidden sheets (I hadn't until this point realised that there were hidden sheets!). I later discovered that the XLSX and ODS also retained the hidden sheets ...but they were (of course) hidden so I didn't immediately notice them! 

Tab delimited and comma separated values - tsv and csv

It is made clear on export that only the current sheet is exported so if using this as an export strategy you would need to ensure you exported each individual sheet one by one.

The tab delimited export of the flexisheet surprised me. In order to look at the data properly I tried importing it into MS Excel. It came up with a circular reference warning which surprised me - were some of the dynamic properties of the sheets being somehow retained (all be it in a way that was broken)?

tab_delim_error_when_import_to_Excel.png
A circular reference warning when opening the tab delimited file in Microsoft Excel

Both of these formats did a reasonable job of capturing the simple menu choices data (though note that the comments were not retained) but neither did an acceptable job of representing the complex data within the flexisheet (given that the more complex elements such as formulas and colours were not retained).

What about the metadata?

I won't go into detail again about the other features of a Google Sheet that won't be saved with these export options - for example information about who created it and when and the complete revision history that is available through Google Drive - this is covered in a previous post. Given my findings when I interviewed a researcher here at the University of York about their use of Google Sheets, the inability of the export options to capture the version history will be seen as problematic for some use cases.

What is the best export format for Google Sheets?

The short answer is 'it depends'.

The export options available all have pros and cons and as ever, the most suitable one will very much depend on the nature of the original file and the properties that you consider to be most worthy of preservation.


  • If for example the inclusion of comments is an essential requirement, XLSX or ODS will be the only formats that retain them (with varying degrees of success). 
  • If you just want a static snapshot of the data in its final form, PDF will do a good job (you must specify that all sheets are saved), but note that if you want to include hidden sheets, HTML may be a better option. 
  • If the data is required in a usable form (including a record of the formula used) you will need to try XLSX or ODS but note that calculated values present in the original sheet may be missing. Similar but not identical results were noted with XLSX and ODS so it would be worth trying them both and seeing if either is suitable for the data in question.


It should be possible to export an acceptable version of the data for a simple Google Sheet but for a complex dataset it will be difficult to find an export option that adequately retains all features.

Exporting Google Sheets seems even more problematic and variable than Google Documents and for a sheet as complex as my flexisheet it appears that there is no suitable option that retains the functionality of the sheet as well as the content.

So, here's hoping that native Google Drive files appear on the list of World's Endangered Digital Species...due to be released on International Digital Preservation Day! We will have to wait until tomorrow to find out...



A disclaimer: I carried out the best part of this work about 6 months ago but have only just got around to publishing it. Since I originally carried out the exports and noted my findings, things may have changed!



Jenny Mitcham, Digital Archivist

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