View git History commands and git internal objects

View git history

 

Git log [branch]/[commit hash]/[tag]Displays a summary of Historical submission information for a branch, commit, or tag.

Git log a .. BDisplay historical information in a-B Evolution

 Add the parameter-P to view the detailed modification information.

Git show [branch]/[commit hash]/[tag]Display details of the last submission

The variable head indicates the Branch currently being processed. If it is a multi-channel merge head ^ n tableThe Nth ancestor, head ~ N indicates the ancestor of the N generation

Git grep "keyword" [branch]/[commit hash]/[tag]Filter and find the corresponding keywords. Various options of grep are supported.

 

Git Object Database

 

Git uses four types of objects to manage the system

Git cat-file can be used to view corresponding files,-T is used to list object types, and-P is used to print objects

You can use git show to obtain the 160-bit hash value, which indicates a commit object.

• The commit object will point to a tree object, that is, the image of the tree directory of the current node in the history; it will also point to the parent commit to establish an association with the previous commit.
• The tree object is used to display the status of a directory. The tree object contains blob objects and subdirectory objects.
• Blob objects contain file data.
• The head of each branch is stored in. Git/refs/heads. At the same time, the headers of the current branch are stored in. Git/head.

 

Git index file

 

For the role of the index file, see the other two documents. for reference:

 

Located in./git/index. You can use the command git LS-files -- stage to view the hash list. Use Git-catfile to view the hash list and get the latest modification.

Therefore, the role of git add is to create a blob file to record the latest changes.CodeAnd add a link to this blob in index file.