Introduction to SQL with videos

How to use GETDATE in SQL The GETDATE() function is one of the most commonly used date and time functions in SQL Server. It returns the current system timestamp of the server on which the SQL Server instance is running. Whether you’re logging entries, filtering data by time, or performing date calculations, GETDATE() is an

How to Use the SQL REPLACE Function  Working with text data in SQL often requires cleaning, transforming, or modifying strings. One of the most commonly used string functions for these tasks is REPLACE. The REPLACE function allows you to substitute all occurrences of a specific substring with another substring, directly within your SQL queries—making it

How to write SQL CASE and IF statements and which Is best When working with SQL to analyze, manipulate, or transform data, one common requirement is to apply conditional logic. This is where SQL’s built-in conditional expressions come into play—most notably the CASE expression and the IF() function. These tools allow you to evaluate values

How to convert data types in SQL In relational databases, data types define how the data is stored, processed, and retrieved. But real-world data is often messy or inconsistent, coming from various sources like APIs, flat files, or user input forms. In such scenarios, type conversion becomes an essential part of SQL development. Two core

Top SQL data types you need to understand When designing databases with SQL Server, choosing the right data type is essential for data accuracy, efficient storage, performance tuning, and long-term maintainability. This guide covers all the major SQL Server data types, grouped by category, with extended use cases and example code. Learn SQL online For

How to work out date differences in SQL with datediff Temporal data is at the heart of many data engineering and analytics tasks—whether it’s measuring user engagement, tracking system uptime, or calculating financial returns over time. One of the fundamental operations in time-based analysis is determining the difference between two dates or timestamps. This is

Is SQL TRUNCATE More Powerful than DELETE ? When managing and manipulating data in SQL databases, two common operations used to remove records are DELETE and TRUNCATE. While they may seem similar at first glance—both remove data from a table—their behavior, performance implications, and use cases differ significantly. This article explores the differences between TRUNCATE

What Is the Point of the SQL RIGHT OUTER JOIN? Structured Query Language (SQL) provides a range of tools to help us work with data stored in relational databases. One of the most powerful features in SQL is the ability to join data from multiple tables. SQL joins are fundamental to combining and analyzing related

Is SQL SUBSTRING the Most Useful SQL Function? When working with data stored in relational databases, SQL provides a rich toolbox of functions to manipulate and transform data. Among them, the SUBSTRING function stands out for its simplicity and versatility. But is it the most useful SQL function? That depends on context—but there’s no denying

Don’t get left behind, learn SQL for beginners If you’re new to working with data, one of the first tools you’re likely to encounter is SQL, which stands for Structured Query Language. SQL is the standard language used to communicate with relational databases. Whether you’re analyzing employee records, customer data, or sales transactions, SQL provides