Recovering lost commits with reflog in Git - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is git reflog used for?

git reflog shows a log of all recent changes to the HEAD, including commits, resets, and checkouts. It helps find lost commits.

beginner

How can you recover a lost commit using git reflog?

Find the commit hash in git reflog, then use git checkout <commit-hash> or git reset --hard <commit-hash> to restore it.

intermediate

What does the command git reset --hard <commit-hash> do?

It moves the current branch to the specified commit and resets the working directory and staging area to match that commit, discarding changes.

beginner

Why might commits become 'lost' in Git?

Commits can become lost after actions like git reset, git rebase, or branch deletion, but they still exist in reflog for a time.

intermediate

How long does Git keep reflog entries by default?

By default, reflog entries are kept for 90 days before they expire and are removed.

What command lists recent HEAD changes including lost commits?

A git reflog

B git log

C git status

D git branch

git reflog shows recent HEAD changes, helping find lost commits.

Which command restores your branch to a lost commit found in reflog?

A git clone <repo>

B git push origin main

C git merge <commit-hash>

D git checkout <commit-hash>

git checkout <commit-hash> lets you move to that commit to recover it.

What does git reset --hard <commit-hash> do?

A Creates a new commit

B Moves branch and resets files to that commit

C Deletes the commit permanently

D Shows commit details

This command moves the branch pointer and resets files to the specified commit.

Why might a commit be missing from git log but visible in git reflog?

A Because the commit is tagged

B Because the commit was pushed

C Because the branch was reset or changed

D Because the commit is merged

Resetting or changing branches can hide commits from git log but reflog still tracks them.

How long does Git keep reflog entries by default?

A 90 days

B 7 days

C Forever

D 30 days

Git keeps reflog entries for 90 days by default before cleaning them up.

Explain how to find and recover a lost commit using git reflog.

Think about how reflog tracks HEAD movements and how to move back to a commit.

Describe why commits might become lost and how reflog helps in recovery.

Consider what happens to commits after branch changes and how reflog records history.