Online Tutorial for Data Analysis and Automation
CHAPTER 28 of 30 SQL Tutorial — Free Course on Neotech Navigators A SQL subquery (also called a nested query or inner query) is a query placed inside another SQL statement. The inner query runs first and its result is used by the outer query. In this chapter, you will learn subqueries in WHERE, SELECT, […]
CHAPTER 27 of 30 SQL Tutorial — Free Course on Neotech Navigators The SQL EXISTS operator tests whether a subquery returns any rows at all. It returns TRUE if the subquery produces one or more rows, and FALSE if it produces zero rows. EXISTS is commonly used to check for related records in another table. […]
CHAPTER 26 of 30 SQL Tutorial — Free Course on Neotech Navigators The SQL HAVING clause filters groups created by GROUP BY based on aggregate conditions. While WHERE filters individual rows before grouping, HAVING filters after aggregation. In this chapter, you will learn the HAVING syntax, understand HAVING vs WHERE, and see practical examples with […]
CHAPTER 25 of 30 SQL Tutorial — Free Course on Neotech Navigators The SQL GROUP BY clause groups rows that share the same value in one or more columns, then lets you run aggregate functions like COUNT, SUM, AVG, MIN, and MAX on each group. In this chapter, you will learn the GROUP BY syntax, […]
CHAPTER 24 of 30 SQL Tutorial — Free Course on Neotech Navigators The SQL FULL OUTER JOIN returns all rows from both tables, matching rows where possible and filling in NULL where there is no match on either side. It combines the behavior of LEFT JOIN and RIGHT JOIN. In this chapter, you will learn […]
CHAPTER 23 of 30 SQL Tutorial — Free Course on Neotech Navigators The SQL RIGHT JOIN returns all rows from the right table and the matching rows from the left table. If there is no match, the left columns are filled with NULL. In this chapter, you will learn the RIGHT JOIN syntax, see practical […]
Learn what SQL JOINs are and why they matter. Understand how to combine rows from two or more tables using INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN with visual examples.
Learn SQL aliases to give temporary names to columns and tables using the AS keyword. Make query output readable and simplify complex queries. Free tutorial with examples.
Learn the SQL BETWEEN operator to filter values within a range. Use BETWEEN with numbers, dates, and text. Combine with NOT BETWEEN for exclusions. Free tutorial.
Learn the SQL IN operator to filter rows by a list of values. Replace multiple OR conditions with a clean IN clause. Free tutorial with practical examples.