PostgreSQL Internals

In PostgreSQL, hash joins are used to join two tables based on a join condition that involves equality comparisons. The optimizer automatically chooses this join method if it determines that a hash join would be […]

Optimizer index caching in PostgreSQL is the process by which the database caches the index pages in memory to speed up the execution of queries. This feature helps improve the performance of queries by reducing […]

In PostgreSQL, the optimizer uses cardinality estimates to determine the most efficient execution plan for a query. Cardinality refers to the number of rows in a table or the number of rows returned by a […]

Cache Buffer Chains (CBC) is a mechanism used by the PostgreSQL storage engine to manage the buffer cache and minimize the amount of disk I/O. The buffer cache is a region of memory that is […]

PgBouncer is a lightweight connection pooler for PostgreSQL. It is used to reduce the overhead of establishing a new connection to a PostgreSQL database for each client request. By pooling connections, PgBouncer can handle a […]

The source code for the PostgreSQL LALR(1) parser is written in C and can be found in the PostgreSQL source code repository. The main components of the parser are: To understand how the parser works, […]

The freelists in PostgreSQL are implemented as a linked list of pages. Each page is a unit of disk space that is managed by the freelist, and its size is determined by the block size […]