As a full-stack developer, you‘ll frequently write SQL queries to retrieve data from relational databases. One of the most important concepts to understand is how to combine multiple conditions using logical operators like AND. The AND operator is used in the WHERE clause of a SELECT, UPDATE, or DELETE statement to specify that all of…
As a full-stack developer, I can confidently say that learning to query data has been one of the most valuable skills in my coding toolkit. Being able to quickly retrieve and analyze information from databases has made me more efficient, more insightful, and more impactful in my work. But I remember how daunting queries seemed…
As a full-stack developer, you know the importance of efficiently searching and manipulating data in databases. One common task is searching for substrings within text fields, whether for user searches, data analysis, or data cleansing. Substring searching is a fundamental skill for any SQL developer. A StackOverflow survey found that over 60% of developers use…
The WHERE clause is one of the most important and commonly used components of SQL queries. It allows you to filter and retrieve specific records from a database table based on defined conditions. Mastering the WHERE clause is essential for any developer working with SQL, as it enables you to write targeted, efficient queries. In…
As a full-stack developer, one of the most crucial architectural decisions you‘ll make when building an application is choosing the right database. The two main contenders are SQL relational databases and NoSQL non-relational databases. Each has its strengths and weaknesses, and the right choice depends on your specific application requirements. In this article, we‘ll dive…
The SQL UPDATE statement is one of the most powerful tools in a developer‘s arsenal, allowing us to modify data in our databases with speed and precision. But as the saying goes, "with great power comes great responsibility." Incorrectly updating data can have disastrous consequences, from introducing bugs to irrevocably corrupting critical information. In this…
As a full-stack developer or data analyst, you‘ll frequently need to modify existing data in your SQL databases. That‘s where the UPDATE statement comes in. Mastering UPDATE is a critical skill that will allow you to keep your data current, fix errors, and respond to changing business requirements. In this comprehensive guide, we‘ll dive deep…
As a full-stack developer, SQL is an indispensable part of your toolkit. Among the many powerful features of SQL are the UNION and UNION ALL operators, which allow you to combine the results of multiple queries into a single result set. While they may seem straightforward at first glance, these operators have nuances and performance…
SQL triggers are special stored procedures that are automatically executed by the database engine in response to specified events. They allow you to enforce business rules, automate maintenance tasks, and add an extra layer of control over data changes. A trigger is associated with a single table and fires whenever that table is modified by…
As a full-stack developer, you know how important it is to work efficiently with databases. Structured Query Language (SQL) is the standard for querying relational databases, but writing complex queries can be time-consuming and result in convoluted, hard-to-read code. Over years of working with SQL, I‘ve picked up many tips and tricks that have helped…
As a full-stack developer and professional coder, I‘ve found temporary tables to be an indispensable tool in my SQL toolkit. They offer a flexible and efficient way to store and manipulate intermediate results, break complex queries into manageable steps, and provide a transient workspace without affecting permanent data. In this expert guide, we‘ll take a…
As a full-stack developer, you‘ll often need to calculate sums and totals from data stored in a SQL database. The SUM() function is one of the most useful aggregate functions in SQL for performing these types of calculations. In this article, I‘ll explain what the SUM() function does and provide many examples of how to…