2 min
SQL
How to do a FULL OUTER JOIN in MySQL?
Problem How to do a FULL OUTER JOIN in MySQL? Let’s create two example tables, employees and departments, and insert some data into them....
2 min
3 min
SQL
How to get the rows which have the max value for a column for each group in another column in SQL?
Problem You want to find the rows that have the maximum value for a specific column within each group in another column. For example,...
2 min
SQL
How to concatenate text from multiple rows into a single text string in MySQL?
Problem You need to concatenate text from multiple rows into a single text string, for every group present in another column using SQL. For...
2 min
SQL
How to switch rows and columns in SQL?
Problem How to switch rows and columns in SQL so that the rows and columns are interchanged? Given a table named Students with columns...
3 min
SQL
How to retrieve the last record in each group in SQL?
Problem You have a table with multiple rows of data for each group, and you want to select the last row from each group....
3 min
SQL
How to get the top 1 row of each group in SQL?
Problem From the test_scores table below, select the top 1 row in each group. For example, you have a table with data about ‘students’...
3 min
SQL
How to select first row in each ‘Group By’ group?
Problem You have a table with multiple rows of data for each group, and you want to select the first row from each group....
2 min
SQL
How to transpose columns to rows in SQL?
Problem How to transpose columns to rows in SQL? This essentially requires reshaping the table in such a way that certain columns of a...
2 min
SQL
How to select only rows with max value on a column?
Problem How to select only rows with max value on a column for each distinct value in another categorical column in MySQL? From Items...
13 min
SQL
SQL Window Function Exercises and Solutions – Set 2
SQL window functions exercises is designed to challenge your SQL muscle and help internalize data wrangling using window functions in SQL. The questions are...
5 min
SQL
SQL Window Functions Exercises – Practice to perfection
SQL window functions is considered a ‘hard’ concept in SQL. This set of exercises is designed to challenge your SQL muscle and help internalize...
14 min
SQL
SQL Window Functions – Made simple and intuitive
SQL window functions is one of the advanced concepts, understanding which will give you the ability to do complex data wrangling and transformations in...
7 min
SQL
SQL Subquery – How to write subqueries using simple examples
SQL Subquery, also known as inner query or nested query, are used to query data from one or more tables and then used in...
25 min
SQL
SQL Tutorial – A Simple and Intuitive Guide to the Structured Query Language
SQL, short for Structured Query Language is a programming language used to communicate with databases and do various types of Data wrangling operations. This...
machine learning +
Cook’s Distance for Detecting Influential Observations
machinelearningplus.com
4 min
Machine Learning
Cook’s Distance for Detecting Influential Observations
Cook’s distance is a measure computed to measure the influence exerted by each observation on the trained model. It is measured by building a...
machine learning +
How to detect outliers with z-score
machinelearningplus.com
6 min
Machine Learning
How to detect outliers with z-score
Z score, also called as standard score, is used to scale the features in a dataset for machine learning model training. It can also...
machine learning +
How to detect outliers using Z score?
machinelearningplus.com
6 min
Machine Learning
How to detect outliers using Z score?
Z score is one of the most important concepts in statistics. It is also called standard score. Typically it is used to scale the...
machine learning +
How to detect outliers using IQR and Boxplots?
machinelearningplus.com
6 min
Machine Learning
How to detect outliers using IQR and Boxplots?
Let’s understand what are outliers, how to identify them using IQR and Boxplots and how to treat them if appropriate. 1. What are outliers?...
2 min
Python
install pip mac – How to install pip in MacOS?: A Comprehensive Guide
Pip is a widely used package manager for Python, allowing you to install and manage Python packages easily. In this blog post, we’ll explore...
machine learning +
Scrapy vs. Beautiful Soup: Which is better for web scraping?
machinelearningplus.com
8 min
Python
Scrapy vs. Beautiful Soup: Which is better for web scraping?
Web scraping is the technique of extracting data from a specific website or web page. This has wide applications in: Research and publication purposes...
