Merge vs Squash Merge in Git: Key Differences and Usage

In Git, a merge combines the full history of a feature branch into the main branch, preserving all commits. A squash merge condenses all feature branch commits into a single commit before merging, keeping the main branch history cleaner.

Quick Comparison

Here is a quick side-by-side comparison of merge and squash merge in Git.

Factor	Merge	Squash Merge
Commit History	Preserves all individual commits from the feature branch	Combines all commits into one single commit
Branch History	Feature branch history is fully retained	Feature branch history is not retained in main branch
Conflict Resolution	Conflicts resolved once during merge	Conflicts resolved once during squash merge
Revertability	Easier to revert individual commits	Revert affects entire squashed commit
Use Case	When full history is important	When a clean, simple history is preferred
Command Example	git merge feature-branch	git merge --squash feature-branch

Key Differences

The main difference between merge and squash merge lies in how they handle commit history. A merge brings all commits from the feature branch into the main branch, preserving the detailed history of changes. This is useful when you want to keep track of every step made during development.

On the other hand, a squash merge takes all the commits from the feature branch and combines them into a single commit before adding it to the main branch. This results in a cleaner, simpler history that looks like one big change instead of many small ones.

While both methods require resolving conflicts if they arise, the squash merge does not keep the original branch's commit history, which can make reverting specific changes harder. Choosing between them depends on whether you value detailed history or a tidy project log.

Code Comparison

Here is how you perform a normal merge in Git:

bash

git checkout main
git merge feature-branch

Output

Updating abc1234..def5678
Fast-forward
 file.txt | 2 ++
 1 file changed, 2 insertions(+)

Squash Merge Equivalent

Here is how you perform a squash merge in Git:

bash

git checkout main
git merge --squash feature-branch
git commit -m "Add feature from feature-branch"

Output

[main abcdef1] Add feature from feature-branch
 1 file changed, 2 insertions(+)

When to Use Which

Choose merge when you want to keep a detailed history of all changes made in the feature branch, which helps in tracking and debugging. It is ideal for collaborative projects where understanding the development process is important.

Choose squash merge when you prefer a clean and simple main branch history, especially for small features or fixes. This keeps the project log easy to read and avoids clutter from many small commits.

Key Takeaways

Use merge to preserve full commit history from feature branches.

Use squash merge to combine all changes into one commit for a cleaner history.

Merging keeps detailed history, squash merging simplifies the main branch log.

Squash merge requires a manual commit after merging the changes.

Choose based on whether detailed history or simplicity is more important for your project.