PostgreSQL Index Scan Types Explained!

In this sql indexes explained video we'll tell you a little about postgresql sql index scan types.

In this PostgreSQL tutorial, you will also learn that sql indexes can be used in one of three ways: the PostgreSQL database can perform a SQL index scan, an index-only scan, or a bitmap SQL index scan. These SQL index scan methods are similar no matter if we're using postgresql server or mysql server - a couple of things will differ, but postgresql vs mysql isn't too different here.

1) Index scan: this mini postgresql course will tell you that the SQL index scan is what we mean by saying "this SQL query uses an index." In other words, if a SQL index scan is involved, data is accessed using a pointer to it, that is, using a SQL index.

2) Index-only scan: this postgresql tutorial for beginners will also tell you that the next method our SQL databases can employ is the index-only scan. Such a method is used if all of the data that is asked for by the query exists in the index itself.

3) Bitmap index scan: this postgresql crash course will also tell you that the SQL query planner will choose the bitmap SQL index scan if a SQL query asks to retrieve a lot of data, but does not process data in the entire table.
Think of the bitmap SQL index scan as something in between the index scan and the index-only scan.

We hope that this postgres tutorial has taught you something to improve your postgres architecture, stick around for more content, and until next time.

Below you will find a couple of sql interview questions and answers for your next sql interview:

Q: What are some of the main database slowness reasons?
A: We've already made a video on this, but the main database slowness reasons are as follows:
1. Selecting too much data
2. Selecting unnecessary data
3. Scanning through many unnecessary rows

To reduce slow sql queries, make sure to use sql indexes.

Q: What is a sql index?
A: sql indexes explained goes like this: a sql index is a database structure used to quickly find rows in a table within a database.

Music:
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