A bitmap index is a special kind of database index that uses bitmaps. Bitmap indexes have traditionally been considered to work well for low-cardinality columns, which have a modest number of distinct values, either absolutely, or relative to the number of records that contain the data. The extreme case of low cardinality is Boolean data (e.g., does a resident in a city have internet access?), which has two values, True and False. Bitmap indexes use bit arrays (commonly called bitmaps) and answer queries by performing bitwise logical operations on these bitmaps. Bitmap indexes have a significant space and performance advantage over other structures for query of such data. Their drawback is they are less efficient than the traditional B-tree indexes for columns whose data is frequently updated: consequently, they are more often employed in read-only systems that are specialized for fast query - e.g., data warehouses, and generally unsuitable for online transaction processing applications. Some researchers argue that bitmap indexes are also useful for moderate or even high-cardinality data (e.g., unique-valued data) which is accessed in a read-only manner, and queries access multiple bitmap-indexed columns using the AND, OR or XOR operators extensively. Bitmap indexes are also useful in data warehousing applications for joining a large fact table to smaller dimension tables such as those arranged in a star schema. (Wikipedia).
Computing z-scores(standard scores) and comparing them
Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Computing z-scores(standard scores) and comparing them
From playlist Statistics
Identify the Level of Measurement MyMathlab Statistics Homework
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From playlist Statistics
What is Prime Factorisation? | Don't Memorise
✅To learn more about Factorisation, enroll in our full course now: https://infinitylearn.com/microcourses?utm_source=youtube&utm_medium=Soical&utm_campaign=DM&utm_content=7n5Qak9hnEU&utm_term=%7Bkeyword%7D In this video, we will learn: 0:00 Introduction 0:14 what are the factors? 0:57 w
From playlist Playing with Numbers
Micrometer/diameter of daily used objects.
What was the diameter? music: https://www.bensound.com/
From playlist Fine Measurements
Ex: Determine the Value of a Number on a Logarithmic Scale (Log Form)
This video explains how to determine the value of several numbers on a logarithmic scale scaled in logarithmic form. http://mathispower4u.com
From playlist Using the Definition of a Logarithm
Micrometer / diameter of daily used objects
What was the diameter? music: https://www.bensound.com/
From playlist Fine Measurements
Statistics Lecture 3.3: Finding the Standard Deviation of a Data Set
https://www.patreon.com/ProfessorLeonard Statistics Lecture 3.3: Finding the Standard Deviation of a Data Set
From playlist Statistics (Full Length Videos)
Math Is Fun: How Mega is a Number? MegaFavNumbers
How big can a number get? #MegaFavNumbers #MegaFavNumbers playlist https://www.youtube.com/playlist?list=PLar4u0v66vIodqt3KSZPsYyuULD5meoAo
From playlist MegaFavNumbers
Asteroids part 13 - It worked first try!? (kind of)
It's time to create another project using the BBECS crate! We'll be making the arcade game of asteroids! links * Code - [https://github.com/brooks-builds/](https://github.com/brooks-builds/) * BBECS - [https://crates.io/crates/bbecs](https://crates.io/crates/bbecs) *
From playlist asteroids
Vernier caliper / diameter and length of daily used objects.
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From playlist Fine Measurements
True Colour and Indexed Colour Bitmaps
This is the second in a sequence of videos about images. It begins by reviewing the impact of resolution (pixel density) and colour depth (the number of bits used to encoded the colour of each pixel) on the quality of an image. It goes on the explain that a true colour 24 bit RGB bitmap
From playlist Images
Asteroids part 15 - Deleting entities from the bitmap
It's time to create another project using the BBECS crate! We'll be making the arcade game of asteroids! links * Code - [https://github.com/brooks-builds/](https://github.com/brooks-builds/) * BBECS - [https://crates.io/crates/bbecs](https://crates.io/crates/bbecs) *
From playlist asteroids
Everything You Need to Know About JPEG - Episode 3: Bitmap Output
In this series you will learn all of the in-depth details of the complex and sophisticated JPEG image compression format In this episode, we learn how to write all of the pixel data in the MCUs to a bitmap file Jump into the playlist here: https://www.youtube.com/watch?v=ldsdJqGr9uc&list
From playlist Fourier
Coding Math: Episode 21 - Bitmap Collision Detection
Some weeks back I promised to show you how to do collision detection with bitmaps in canvas. Here you go! Support Coding Math: http://patreon.com/codingmath Source Code: http://github.com/bit101/codingmath
From playlist Episodes
PGConf NYC 2021 - Flexible Indexing with Postgres by Bruce Momjian
Flexible Indexing with Postgres by Bruce Momjian When considering database indexing, many people are confused by the many Postgres indexing structures available, and the many data-type-specific index lookup methods. For example, brin allows for efficient indexing of many columns. gin inde
From playlist PGConf NYC 2021
Live Stream: Preparing for a ECS Rust tutorial part 6
I'm going to be making a real tutorial for how to build a ECS from scratch. This is going to be the raw series of live streams uncut and unedited. After we will record videos for the tutorial which will go into a different playlist. Links * BBECS: [https://github.com/brooks-bui
From playlist Uncut Live Streams
RubyConf 2022: Data indexing with RGB (Ruby, Graphs and Bitmaps) by Benjamin Lewis
In this talk, we will go on a journey through Zappi’s data history and how we are using Ruby, a graph database, and a bitmap store to build a unique data engine. A journey that starts with the problem of a disconnected data set and serialised data frames, and ends with the solution of an i
From playlist RubyConf 2022: Mini and Houston
Asteroids part 11 - Starting to create a BitMap
It's time to create another project using the BBECS crate! We'll be making the arcade game of asteroids! links * Code - [https://github.com/brooks-builds/](https://github.com/brooks-builds/) * BBECS - [https://crates.io/crates/bbecs](https://crates.io/crates/bbecs) *
From playlist asteroids
PGConf NYC 2021 - Identifying Slow Queries and Fixing Them! by Stephen Frost
Identifying Slow Queries and Fixing Them! by Stephen Frost We'll be looking at PostgreSQL configuration options (postgresql.conf) for logging and basic tuning parameters, how to monitor which queries are taking the most time using pg_stat_statements, going over EXPLAIN and EXPLAIN ANALYZE
From playlist PGConf NYC 2021
Find x given the z-score, sample mean, and sample standard deviation
Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Find x given the z-score, sample mean, and sample standard deviation
From playlist Statistics