We provide three options for learning SQL. Here you will find our free article-based SQL language course. This consists of a number of articles that will get you started in your journey to learn SQL. If you are looking to go into more detail, practice with worked examples and elevate your skills to an expert […]
Best SQL language course Read More »
SQL (Structured Query Language) is a powerful tool for managing and querying relational databases. One of the fundamental operations in SQL is the SELECT statement, which allows you to retrieve data from a database. In this article, we will explore how to use SQL SELECT statements to retrieve, sort and filter data. We will look
1 – SQL SELECT, SQL WHERE, and ORDER BY Read More »
In SQL, grouping data is a powerful operation that allows you to aggregate and analyse data effectively. This is especially useful when you want to generate aggregated data or perform calculations. You can also filter the returned aggregations based on the aggregated results rather than individual row details. This cannot be done with the WHERE
2- SQL group by and SQL having clause Read More »
Subqueries, sometimes referred to as nested queries or inner queries, are a useful feature in SQL that allows you to deal with more complex data retrieval and manipulation tasks. They are a useful tool for any SQL developer or database administrator, enabling you to write more sophisticated queries. This article will provide an in-depth understanding
So far we have largely looked at selecting data from a single table. In this article, we will look at how data can be combined from multiple tables with the use of SQL joins. There are different ways of joining data together including the INNER JOIN, LEFT OUTER JOIN, RIGHT OUTER JOIN, FULL OUTER JOIN
4 – SQL JOINS – INNER, OUTER, LEFT, RIGHT, FULL and CROSS Read More »
In this guide, you will learn the syntax and see some practical examples of how to use the SQL insert data command. We will introduce some new Keywords including INSERT INTO and look at how you can insert a single or multiple rows. SQL Insert data table of contents Learn SQL online For our instructor
5 – SQL Insert data Read More »
In this article, we will explore how to update and delete data using SQL, providing both theoretical insights and practical examples to help you become proficient in these essential database tasks. Updating allows you to modify existing records while deleting allows you to remove unwanted data from your database. You should always exercise caution when
6 – SQL Update command and SQL Delete row Read More »
In this article, we will explore the process of creating and altering tables in SQL Server, including an explanation of data types, practical examples, and best practices. In a relational database, data is organized into tables. Each table comprises rows and columns, where each row represents a unique record, and each column defines a specific
7 – SQL Create table and Alter table Read More »
