Sql Programming Tutorials, Guides & Best Practices

SELECT * FROM your_table_name
INTO OUTFILE '/path/to/export.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n';

• /path/to/export.csv: The file where the data will be exported.

EXPLAIN SELECT name, salary
FROM employees
WHERE department = 'Engineering' AND salary > 70000
ORDER BY salary DESC;

SELECT name, salary
FROM employees
WHERE department = 'Engineering' AND salary > 70000
ORDER BY salary DESC
LIMIT 5;

• ROW_NUMBER(): Assigns unique sequential numbers.
• RANK(): Assigns ranks with gaps on ties.
• DENSE_RANK(): Ranks without gaps.
• NTILE(n): Divides rows into n groups.
• LEAD() / LAG(): Accesses next/previous rows.

SELECT column1, window_function() OVER (PARTITION BY column ORDER BY column)
FROM table;

In this tutorial, we will explore various types of SQL joins, understand their syntax, and learn through examples. By the end of this guide, you will have a solid understanding of how to use joins to fetch related data across tables efficiently.

In a relational database, data is organized in tables. Each table consists of rows and columns, with each row representing a unique record. Tables can be related to each other through keys, typically primary and foreign keys. Joins allow us to combine rows from two or more tables based on a related column between them.