Top 15 SQL Queries for Data Analysts

Data analysts need to use SQL (Structured Query Language) in order to access, modify, and evaluate data stored in relational databases. Knowing and being proficient with these top 15 SQL queries is crucial, regardless of whether you're new to SQL or want to improve your data analysis abilities. We will examine SQL queries that are particularly helpful for data analysts in this article

• SELECT statement: Retrieve data from a single table.

SELECT * FROM table_name;

• WHERE clause: Filter rows based on a condition

SELECT * FROM table_name WHERE condition;

• ORDER BY clause: Sort the result set.

SELECT * FROM table_name ORDER BY column_name;

• GROUP BY clause: Group rows that have the same values into summary rows.

SELECT column_name, COUNT(*) FROM table_name GROUP BY column_name;

• HAVING clause: Filter groups based on a condition.

SELECT column_name, COUNT(*) FROM table_name GROUP BY column_name HAVING condition;

• JOIN clause: Combine rows from two or more tables based on a related column.

SELECT * FROM table1 JOIN table2 ON table1.column_name = table2.column_name;

• INNER JOIN: Return rows when there is a match in both tables.

SELECT * FROM table1 INNER JOIN table2 ON table1.column_name = table2.column_name;

• LEFT JOIN: Return all rows from the left table, and the matched rows from the right table.

SELECT * FROM table1 LEFT JOIN table2 ON table1.column_name = table2.column_name;

• RIGHT JOIN: Return all rows from the right table, and the matched rows from the left table.

SELECT * FROM table1 RIGHT JOIN table2 ON table1.column_name = table2.column_name;

• FULL OUTER JOIN: Return all records when there is a match in either left or right table.

SELECT * FROM table1 FULL OUTER JOIN table2 ON table1.column_name = table2.column_name;

• UNION operator: Combine the result sets of two or more SELECT statements.

SELECT FROM table1 UNION SELECT FROM table2;

• UNION ALL operator: Combine the result sets of two or more SELECT statements (including duplicates).

SELECT column1, column2, ... FROM table1

UNION ALL

SELECT column1, column2, ... FROM table2;

• COUNT() function: Count the number of rows in a table.

SELECT COUNT(*) FROM table_name;

• SUM() function: Calculate the sum of values in a column.

SELECT SUM(column_name) FROM table_name;

• AVG() function: Calculate the average value of a column.

SELECT AVG(column_name) FROM table_name;