In this project, you will modify a very simple database system that we have written to illustrate some of the transactions functionality.
In this project, you will modify a very simple database system that we have written to illustrate some of the transactions functionality.
The database system is written in Python and attempts to simulate how a database system would work, including what blocks it would read from disk, etc.
The database system is written in Python and attempts to simulate how a database system would work, including what blocks it would read from disk, etc.
**NOTE**: This codebase is different from the Project 4 codebase, with simpler relation schema and querying interface, but a more complex Buffer Pool Manager, and file management. Also, **this project requires python 2.7**.
**NOTE**: This codebase is different from the Project 4 codebase, with simpler relation schema and querying interface, but a more complex Buffer Pool Manager, and file management. Also, **this project requires python 3.X**.
See some details below.
**Another Important Note:** We have taken a few shortcuts in this code to simplify it, which unfortunately means that there may be important synchronization failures we missed. Let me know if you see any unexpected behavior.
**Another Important Note:** We have taken a few shortcuts in this code to simplify it, which unfortunately means that there may be important synchronization failures we missed. Let me know if you see any unexpected behavior.
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@@ -47,7 +46,7 @@ what locks the transaction currently holds, etc.
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@@ -47,7 +46,7 @@ what locks the transaction currently holds, etc.
#### `testing.py`
#### `testing.py`
This contains some code for testing. You should be able to run: `python testing.py` to get started. Note that the first time you run it, it will create the
This contains some code for testing. You should be able to run: `python3 testing.py` to get started. Note that the first time you run it, it will create the
two files `relation1` and `logfile`, but after you kill it, the logfile will be inconsistent (we never write out CHECKPOINT
two files `relation1` and `logfile`, but after you kill it, the logfile will be inconsistent (we never write out CHECKPOINT
records in normal course). So the second time you run it, it will error out since the restartRecovery code is not implemented. So if you want to work on the other
records in normal course). So the second time you run it, it will error out since the restartRecovery code is not implemented. So if you want to work on the other
two tasks, you should remove those two files every time.
two tasks, you should remove those two files every time.
