Git Merge Vs Git Rebase

The two paths to integrate code in a Git based source control

Do you choose to preserve or rewrite history?

Git is a distributed source control system essential for managing code repositories. Developers create and merge branches to deliver features, enhancements, and bug fixes. While there are several ways to organise branches, a common workflow is to create a branch from main, build and commit changes, then keep it updated with main using rebase or merge. Once the work is complete, the branch is merged back into main through a pull request, ensuring the changes are reviewed and integrated into the stable codebase without conflicts.

Two of the most commonly debated commands are git merge and git rebase. While both aim to integrate changes from one branch into another, they do so in fundamentally different ways. Understanding these differences is crucial for maintaining a clean, understandable project history.

Git Merge

Combines the histories of two branches by creating a new merge commit. Preserves the exact sequence of commits from both branches. The resulting history is non‑linear, showing branches diverging and then converging. Consider the following figure

Git Rebase

Moves or “replays” commits from one branch on top of another. Rewrites history by creating new commits with the same changes but different parent references. This is useful as it maintains history of commits. However, it’s not possible to point out the exact time in code history the feature branch was merged with the main branch.

Please note, the rebase option produces a linear project history, as if the work was done sequentially.

When to use Git Merge?

• You want to preserve the full history of how branches diverged and converged.
• Collaboration (among multiple team members committing to respective feature branches) is ongoing and you don’t want to rewrite commits others may already be using.
• Example: Merging a feature branch into main after a pull request is reviewed.

When to use Git Rebase?

• You want a clean, linear history without extra merge commits.
• You’re working on a personal feature branch and want to keep it up to date with main before merging.
• Example: Rebasing your feature branch onto the latest main to avoid conflicts later.

Consider using git pull — — rebase to keep your local branch updated with remote changes while avoiding unnecessary merge commits.

In conclusion, Both git merge and git rebase serve the same ultimate purpose: integrating changes across branches. The choice depends on your team’s workflow and priorities:

• Merge emphasises preserving history and collaboration safety.
• Rebase emphasises clarity and linearity in history.

In practice, many teams use a combination: rebasing feature branches to stay current, then merging into main to preserve collaborative history.