Author: Movead Li

Recently, some people are asking why the wal of the database is consumed so quickly. This blog gives a simple way to analyze where the wal log is consumed, and you can get the reason for wal expansion. Note: There

When using logical replication with PostgreSQL, the wal level needs to be set to ‘logical’, so the logical level wal contains more data to support logical replication than the replicate wal level. I think it’s unclear to many users or

Transaction is the most basic concept of a database. Using begin and end command in PostgreSQL can start and commit a transaction. Of course, this is the most common PostgreSQL transaction. In addition, there are sub transaction, multi transaction, 2pc

When inserting data into a table, you can specify that the value of a field is null. For example, for a table t (i int, j int, k int), we can execute insert into t values (8,1,6), or insert into

Server Programming Interface(SPI) is a module in the PostgreSQL kernel which allows kernel developers to execute SQL statements in C functions and have the ability to manage transactions. This module provides great convenience for PostgreSQL plug-in development through its characteristics

PostgreSQL will create some catalog and other caches for each connection request to store some queried data locally, which can speed up query efficiency. If a process undergoes a DDL operation that causes catalog to change, other running processes need

While studying the WAL structure, I came across a keyword named “origin” in the WAL log that I found intriguing. There is not much details on PG official documentation on this keyword in the WAL record and its functions. Hence

A table in PostgreSQL has a relfilenode value, which specifies the file name of the table on disk (except foreign table and partition table). In general, this value can be found in the relfilenode field of the pg_class table, but

This is the second part of the topic, the more historical version is described in the previous part, and here is the vitality of wal in PostgreSQL which born replication、logical replication and more performance related configure, let’s continue to redo

WAL is one of the most important parts of PostgreSQL., WAL records all the database activity. Hense we can regard wal as a change roadmap of the history of PostgreSQL database, and the crash recovery, logical replication etc aren’t possible

PostgreSQL Community is working on adding built-in sharding in Postgres and it seems that the community is following the FDW based sharding approach for adding built-in sharding for PG. The Parallel Foreign Scan is a very important part of this

The lock is an essential part of a database system. In PostgreSQL, there are various locks, such as table lock, row lock, page lock, transaction lock, advisory lock, etc. Some of these locks are automatically added to complete the database