Write-Ahead Logging (WAL) Technology: The Magical Tool to Handle Crashes

Write-Ahead Logging (WAL) technology, as a mechanism that records data to a log file before writing it to disk, provides an effective solution to server crash issues. Its core principle seems simple but contains immense power.

Data Durability Assurance

In traditional data writing methods, data is written directly to disk, a process that can be disrupted and fail due to various factors. WAL technology changes this process; when data needs to be written, the system first records the data change information in the log file and then writes the data to disk. Log files typically have higher reliability and durability; even if the server crashes during the data writing process, the data change information is already recorded in the log file. After the server restarts, the system can rewrite the incomplete data to disk based on the contents of the log file, ensuring data integrity and consistency. This is akin to constructing a building by first detailing every step of the construction plan on paper; even if there are unexpected interruptions during construction, the plan allows for accurate restoration, ensuring the building is ultimately completed smoothly. @Walrus 🦭/acc #walrus $WAL