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SQL Interview Success: Unlocking the Top 5 Frequently Asked Queries

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 Here are the five top commonly asked SQL queries in the interviews. These you can expect in Data Analyst, or, Data Engineer interviews. Top SQL Queries for Interviews 01. Joins The commonly asked question pertains to providing two tables, determining the number of rows that will return on various join types, and the resultant. Table1 -------- id ---- 1 1 2 3 Table2 -------- id ---- 1 3 1 NULL Output ------- Inner join --------------- 5 rows will return The result will be: =============== 1  1 1   1 1   1 1    1 3    3 02. Substring and Concat Here, we need to write an SQL query to make the upper case of the first letter and the small case of the remaining letter. Table1 ------ ename ===== raJu venKat kRIshna Solution: ========== SELECT CONCAT(UPPER(SUBSTRING(name, 1, 1)), LOWER(SUBSTRING(name, 2))) AS capitalized_name FROM Table1; 03. Case statement SQL Query ========= SELECT Code1, Code2,      CASE         WHEN Code1 = 'A' AND Code2 = 'AA' THEN "A" | "A

10 Excusive Steps You need for Web Scrapping

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Here're ten Python technics to clean the scraped data. The scraped  Text has unwanted hidden data . So, as part of cleaning it try to remove these ten in your data. 10 Steps for Web scrapping Data is prime input for  text analytics projects . After cleaning, you can feed to Machine/Deep Learning systems. Removing HTML tags Tokenization Removing unnecessary tokens and stop-words Handling contractions Correcting spelling errors Stemming Lemmatization Tagging Chunking Parsing 10 Technics to Clean Text in Python 1. Removing HTML tags The unstructured text contains a lot of noise ( data from web pages, blogs, and online repositories.)when you use web/screen scraping.  The HTML tags, JavaScript, and Iframe tags typically don't add much value to understanding and analyzing text. Our purpose is to remove HTML tags, and other noise. 2. Tokenization Tokens are independent and minimal textual components. And have a definite syntax and semantics. A paragraph of text or a text document has