PT-02 How to read and understand Explain Query Plan in Postgresql

Описание

To read an explained query plan in PostgreSQL, you can use the "EXPLAIN" command followed by the query you want to analyze. The output will show the execution plan that PostgreSQL uses to execute the query, including the sequence of operations it performs and the order in which it accesses tables and indexes.

The most critical information in the explained plan is the "cost" or "estimated cost" of each operation, which gives an idea of how expensive that operation is in terms of CPU and I/O.

It also provides some helpful information like

number of rows
width of rows
type of join used
number of filters
number of sort operations
number of index scans

https://link.medium.com/4J7vJqZVZwb


#postgresql #Explainplan #Queryplan