Coding interview preparation

python-training Python training for business analysts and traders. This is designed to be an introduction to numerical computing and data visualization in Python. It is not designed to be a complete course in Computer Science or programming, but rather a motivational demonstration of how relatively complex topics can be accessible even to those without formal progamming backgrounds. Creator: J.P. Morgan Stars: ⭐️ 2.9k Forked by: 709 GitHub repo: https://github.com/jpmorganchase/python-training #python #training ➖➖➖➖➖➖➖➖➖➖➖➖➖➖ Join @github_repositories_bds for more cool repositories. *This channel belongs to @bigdataspecialist group

JavaScript® Notes for Professionals book 📄 400+ pages 🔗 Book Link #Javascript ➖➖➖➖➖➖➖➖➖➖➖➖➖ Join @web_dev_bds for more

How Query is Executed Order of SQL query execution is not the same as order query is written. You probably noticed that when you write SELECT count(*) AS column_name, you can't use that column_name in WHERE or GROUP BY clause. It's because select clause in which you defined your alias is not executed yet! Each query begins with finding the data that we need in a database, and then filtering that data down into something that can be processed and understood as quickly as possible. Because each part of the query is executed sequentially, it's important to understand the order of execution so that you know what results are accessible where. In general, SQL queries are executed in the following order: 1. FROM: The first step is to identify the tables or views involved in the query. This is specified in the FROM clause of the query. 2. JOIN: If the query involves multiple tables and requires a join operation, the join conditions are evaluated to combine the data from different tables. 3. WHERE: The WHERE clause is applied to filter the rows based on specified conditions. Rows that do not meet the conditions are eliminated from further processing. 4. GROUP BY: If the query includes a GROUP BY clause, the rows are grouped based on the specified columns. 5. HAVING: If a HAVING clause is present, it is applied to filter the groups generated by the GROUP BY clause. Groups that do not meet the conditions are eliminated. 6. SELECT: The SELECT clause is applied to determine the columns to be included in the result set. Any calculations or functions specified in the SELECT clause are also evaluated at this stage. 7. DISTINCT: If the query includes the DISTINCT keyword, duplicate rows are removed from the result set. 8. ORDER BY: If an ORDER BY clause is present, the result set is sorted based on the specified columns. 9. LIMIT/OFFSET: If the query includes a LIMIT and/or OFFSET clause, the result set is limited to a specific number of rows and/or skipped by a certain number of rows. It’s important to note that not all queries will include every step mentioned above. The order of execution may vary depending on the specific query and the presence of different clauses.

Most stressful parts of coding interview Source: hired.com