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This article mainly explains "how to use Explain". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Now let the editor take you to learn how to use Explain.

Implementation Plan (Execution Plan) what implementation plan?

Postgres has a powerful feature that shows you how database content executes a query. The so-called execution plan here is shown through explain, and knowing this will let you know how to optimize database performance through indexes. for most people, the difficulty is to understand these outputs, although most developers know some of the key points.

About interpretation (Explain)

Each query is executed with an execution plan, and there are three forms to output this information through explain:

Regular form (only shows what may have happened)

Analyze (analyze what happens in the actual query)

Verbose (shows a complete internal execution plan tree for advanced users)

In most cases, explain is used to parse SELECT statements, but you can use it in:

INSERT

UPDATE

DELETE

EXECUTE

DECLARE

Use Explain

For example, this query:

SELECT FROM where > = 50000EXPLAIN SELECT FROM where > = 50000 muri-on = 0001650 rows=173 = 118 > = 50000EXPLAIN ANALYZE SELECT FROM where > = 5000muri- -on = 0001650 rows=173 = 1180000180018 rows=0 = 1 > = 500000053 CREATE INDEX on employees (salary)

By doing so, our query time is reduced from 295 milliseconds to 1.7 milliseconds.

At this point, I believe you have a deeper understanding of "how to use Explain". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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