Suppose the following repository
| Action | Path | Copy src path | Copy src revision | |
|---|---|---|---|---|
| Revision 1 | ||||
| A | /trunk | |||
| A | /branches | |||
| A | /tags | |||
| Revision 2 | ||||
| A | /trunk/foo.txt | |||
| A | /trunk/bar.txt | |||
| Revision 3 | ||||
| D | /trunk | |||
| Revision 4 | ||||
| A | /branches/1.0 | /trunk | 2 | |
In this algorithm log messages are first stored without processing them. When the user wants to show a graph the cache information is processed only for that file.
First all log messages are stored without processing them.
| Path | Revision id | Copy src revision | Copy src path | Action | File id |
|---|---|---|---|---|---|
| /trunk | 1 | NULL | NULL | A | NULL |
| /branches | 1 | NULL | NULL | A | NULL |
| /tags | 1 | NULL | NULL | A | NULL |
| /trunk/foo.txt | 2 | NULL | NULL | A | NULL |
| /trunk/bar.txt | 2 | NULL | NULL | A | NULL |
| /trunk | 3 | NULL | NULL | D | NULL |
| /branches/1.0 | 4 | 2 | /trunk | A | NULL |
Suppose the user wants to see the graph for /branches/1.0/foo.txt at revision 4. We ask the repository for the first log message of the selected file. In our case
| Revision number | Action | Path | Copy src path | Copy src revision |
|---|---|---|---|---|
| 2 | A | /trunk/foo.txt |
Now we now that the graph for /branches/1.0/foo.txt starts at revision 2 with the path /trunk/foo.txt
This step calculates all the information for the graph of the selected file.
All revisions (starting in this case at revision 2) are iterated.
This is the first revision of the file. We create a new file_id for this file. And we update the change path when the file was added for the first time.
| File id | Revision from | Revision to | Path |
|---|---|---|---|
| 1 | 2 | NULL | /trunk/foo.txt |
| Path | Revision id | Copy src revision | Copy src path | Action | File id |
|---|---|---|---|---|---|
| /trunk | 1 | NULL | NULL | A | NULL |
| /branches | 1 | NULL | NULL | A | NULL |
| /tags | 1 | NULL | NULL | A | NULL |
| /trunk/foo.txt | 2 | NULL | NULL | A | 1 |
| /trunk/bar.txt | 2 | NULL | NULL | A | NULL |
| /trunk | 3 | NULL | NULL | D | NULL |
| /branches/1.0 | 4 | 2 | /trunk | A | NULL |
| Action | Path | Copy src path | Copy src revision |
|---|---|---|---|
| D | /trunk |
A parent directory is deleted, so we mark /trunk/foo.txt as deleted. We also add a row in the change paths table.
| File id | Revision from | Revision to | Path |
|---|---|---|---|
| 1 | 2 | 3 | /trunk/foo.txt |
| Path | Revision id | Copy src revision | Copy src path | Action | File id |
|---|---|---|---|---|---|
| /trunk | 1 | NULL | NULL | A | NULL |
| /branches | 1 | NULL | NULL | A | NULL |
| /tags | 1 | NULL | NULL | A | NULL |
| /trunk/foo.txt | 2 | NULL | NULL | A | 1 |
| /trunk/bar.txt | 2 | NULL | NULL | A | NULL |
| /trunk | 3 | NULL | NULL | D | NULL |
| /trunk/foo.txt | 3 | NULL | NULL | D | 1 |
| /branches/1.0 | 4 | 2 | /trunk | A | NULL |
| Action | Path | Copy src path | Copy src revision |
|---|---|---|---|
| A | /branches/1.0 | /trunk | 2 |
A parent directory is copied
| File id | Revision from | Revision to | Path |
|---|---|---|---|
| 1 | 2 | 3 | /trunk/foo.txt |
| 1 | 4 | NULL | /branches/1.0/foo.txt |
| Path | Revision id | Copy src revision | Copy src path | Action | File id |
|---|---|---|---|---|---|
| /trunk | 1 | NULL | NULL | A | NULL |
| /branches | 1 | NULL | NULL | A | NULL |
| /tags | 1 | NULL | NULL | A | NULL |
| /trunk/foo.txt | 2 | NULL | NULL | A | 1 |
| /trunk/bar.txt | 2 | NULL | NULL | A | NULL |
| /trunk | 3 | NULL | NULL | D | NULL |
| /trunk/foo.txt | 3 | NULL | NULL | D | 1 |
| /branches/1.0 | 4 | 2 | /trunk | A | NULL |
| /branches/1.0/foo.txt | 4 | 2 | /trunk/foo.txt | A | 1 |
As you can see at the end we have only calculated the branching information of the selected file. The result is: just one file id in the files and change paths table.