Write-Ahead Logging 편집하기 (부분)

==How Write-Ahead Logging Works==
WAL operates with the following principles:
#'''Log Before Data:''' Before any changes are written to the database, the corresponding log entries are recorded.
#'''Atomic Writes:''' The log entry is written atomically to prevent partial updates.
#'''Recovery Mechanism:''' During recovery, the system replays the log to restore committed transactions and roll back uncommitted ones.
'''Example of WAL Workflow'''

# A transaction modifies a row in the database. 
# The system writes a log entry describing the change (e.g., "update row X: old value = A, new value = B"). 
# The log entry is flushed to stable storage. 
# The actual modification is written to the database.

If a crash occurs after step 3 but before step 4, the log ensures that the change can still be applied during recovery.