This webinar discusses the integration of Git with Excel, emphasizing the importance of treating Excel files as code for effective collaboration and version control. Key topics include the challenges posed by large Excel files, merge conflicts, and best practices such as eliminating versioned file names and using .gitignore for temporary files. Various tools are highlighted, including Git LFS for handling large files and other resources for managing Excel files within Git workflows.

1. Git for Excel
Felix Zumstein, 26 March 2020
Webinar

2. Agenda
2
1. But why?!
2. Git refresher
3. So what’s the issue?
4. Four golden rules
5. Tools
6. Merge conflicts

3. 1. But why?!

4. Look familiar?
4

5. A few more reasons
5
• Excel files are code, so treat them as such
• Git is battle tested
• Collaboration
• Audit trail / Spreadsheet governance
• Peer review / Approval process
• Reduce errors

6. 2. Git refresher

7. The most important commands
7
• git diff
• git add Book1.xlsm
• git commit –m ”changed some things”
• git push origin master
• git pull

8. 3. So what’s the issue?

9. 1) Git doesn’t understand Excel
9

10. 2) GitHub doesn’t understand Excel
10
and GitLab/BitBucket/Azure DevOps are no better

11. 3) Heavy Excel files
11
• Git transfers the entire commit history of the
repository during the cloning process.
• As an example: Committing a 25 MB workbook
once per day during weekdays will lead to 7 GB
repo at the end of the year

12. 4) Merge conflicts
12
Compared to text files, merge
conflicts with Excel files:
• Happen way more often
• Are harder to resolve

13. 4. Four golden rules

14. 1) No more versioned file names!
14
Financial Model_v1.xlsb
Financial Model.xlsb

15. 2) Make use of commit messages
15

16. 3) Add temp files to .gitignore
16
The .gitignore file prevents certain files to be accidentally
added/pushed to Git. To filter out temporary Excel files,
add this to your .gitignore file:
~$*.xl*
Otherwise you’ll end up
sooner or later like this:

17. 4) Release a version via “git tag”
17
Release
asset/artifact
(not part of
Git repo!!)
• It’s OK to include version stamps in released files
• Automate this! See: https://www.xltrail.com/blog/how-
to-manage-and-release-excel-files-on-github-part2

18. 5. Tools

19. A. Spreadsheet Compare

20. Spreadsheet Compare
20
• Compares 2 Excel files
• Standalone desktop app (also integrated into
the Inquire Excel add-in)
• Part of Office Professional Plus and Office 365
ProPlus
• You can integrate it with Git:
https://www.xltrail.com/blog/git-diff-spreadsheetcompare

21. Sheet comparison
21

22. VBA comparison
22

23. B. xltrail

24. xltrail
24
• Free trial: https://www.xltrail.com
• xltrail syncs with any Git provider
• Alternatively, it works via Drag and Drop
and manages Git behind the scenes
• Allows comparisons across branches,
between any two versions

25. Summary across sheets and VBA
25

26. Sheet in context
26

27. C. Git XL

28. Git XL
28
• https://www.xltrail.com/git-xl
• Free & open-source local Git extension
• Created & maintained by us
• It can diff & merge (!) VBA code
• Windows only for now

29. Git XL: via command line
29

30. Git XL: via Sourcetree
30
Zero configuration required!

31. Git XL: VBA merging
31
• Git XL merges VBA directly in the VBA Editor
• Conflicts get highlighted like this:

32. D. Git LFS (Large File Storage)

33. Git LFS intro
33
• https://git-lfs.github.com
• Free & open-source local Git extension
• Large files are downloaded during “git checkout”
rather than during “git clone/git fetch”
• On the server side, you need to make sure that it
is supported & enabled
• git lfs track "*.xl*"
• Side note: Since Git 2.18 (June 2018), there’s an
“emerging feature” built into Git directly that is called
“partial clone”: https://git-scm.com/docs/partial-clone

34. Git LFS in action
34
• All standard Git commands like git pull/push work
automatically with LFS behind the scene

35. E. Git clients

36. Git clients
36
Git offers various clients to interact with the remote:
• Command Line
• Desktop clients (e.g. GitHub Desktop, Sourcetree).
For an overview: https://git-scm.com/downloads/guis
• File explorer integration: https://tortoisegit.org
• Integration with IDE/Text Editor (e.g. VSCode)
• Drag and Drop directly on GitHub, GitLab, Azure
DevOps (but not Bitbucket)

37. 6. Merge conflicts

38. Merge conflicts will bite you!
38
They also happen:
• with a single master branch
• with a single user
For example:
• You commit during the day at work. In the
evening, you continue at home and forget to
pull before you make a new commit.

39. How do merge conflicts happen
39
True
merges
always
cause a
merge
conflict
with
Excel
Files
Fast-forward
merges
never
cause a
merge
conflict

40. A. Single branch workflow:
File locking

41. Informal file locking
41
• Similar to shared drives or SharePoint
• This prevents the merge conflict altogether
• Easy solution:
@team I am going to
update Model.xlsm
Let me know when you’re
done, I need it for 5 min.
All yours.
Thanks, let me pull.

42. Git LFS file locking
42
• Git LFS offers file locking (introduced
with v2.0)
• Meanwhile, all major providers support it
• A caveat of the file locking is that you
need to remember two things:
–Lock the file
–Start with a “git pull” before you edit the file
• git lfs track "*.xl*" --lockable

43. Git LFS file locking: commands
43
User: fzumstein
User: jenny

44. B. Multi branch workflow

45. Merge two branches
45
• We want to merge ”mybranch” into
“master”
• We end up in a merge conflict:

46. git mergetool to the rescue
46
• A simple way to get the files from both
branches next to each other is via “git
mergetool” – then cancel with Ctrl-C.
• This will add 4 files:
master mybranch

47. Resolve the merge conflict
47
• Now compare “contact_list.xlsm” (master)
with “contact_list_REMOTE.xlsm” (mybranch)
• Spreadsheet Compare or xltrail will be helpful
with that
• Manually apply the changes you want from
mybranch in your master version
• Then resolve the merge conflict via “git add”
and “git commit”.
• See: https://www.xltrail.com/blog/merge-excel-workbooks-with-git

48. Thank You
Let’s connect:
https://www.linkedin.com/in/felix-zumstein
More material:
https://www.xltrail.com/blog