8 Dec 2022 Martyna Sławińska How to Export Data From Microsoft SQL Server to a CSV File When working with data and databases, it is common to export data for further processing or transport to another database. Follow this article to learn how to export data from Microsoft SQL Server to a CSV file. In this article, we first recall what a CSV file is and why you would want to export data in this format from an MS SQL Server database. Then, we cut to the chase and export data to a CSV file using both SQL Server Management Studio (SSMS) and SQL Command Line (SQLCMD). Read more 22 Nov 2022 Martyna Sławińska How to Export Data from MySQL into a CSV File A database is a primary platform for working with data and storing data. But often, you must take your data out of the database. Read on to find out how to export data from MySQL database into a CSV file. In this article, we’ll demonstrate how to export data into a CSV file. We’ll start by introducing what a CSV file is and why we use it. Then, we’ll export data from a MySQL database into a CSV file. Read more 15 Sep 2022 Martyna Sławińska How to Import a CSV File to a MySQL Database CSV files store and transfer data between databases. Read on to find out how easy it is to work with CSV files in a MySQL database. CSV files are one of the oldest data exchange formats and are still heavily used by IT professionals from various domains. It is common for online data resources and different database software to offer their data uploads and downloads in CSV format. In this article, we’ll briefly review what a CSV file is and how to work with it. Read more 11 Nov 2021 Martyna Sławińska What Are Aggregate Functions in SQL, and How Do I Use Them? Data is your source of knowledge. And thanks to SQL aggregate functions, you can extract the precise knowledge you need from your data efficiently. Read along to find out more. The core SQL aggregate functions are the following: COUNT(column_name | *) returns the number of rows in a table. SUM(column_name) returns the sum of the values of a numeric column. AVG(column_name) returns the average value of a numeric column. Read more 29 Sep 2021 Martyna Sławińska Why Do Relational Databases Use Primary Keys and Foreign Keys? Relational databases organize data in a standardized manner. All data is entered into tables, the so-called relations. The tables are linked with one another to create connections between the data. The backbone of any relational database is the primary and foreign keys. Read along to find out why they are so important. In this article, we focus on the reasons why relational databases use primary and foreign keys. First, we review what primary and foreign keys are. Read more 12 Aug 2021 Martyna Sławińska An Overview of MS SQL Server Data Types SQL Server data types define what can be stored in a column, local variable, expression, or parameter. It is essential to pick the right data type. Ultimately. your choice of data types affects the whole database. Read on to learn about all of the data types available in MS SQL Server. In this article, we’ll cover numerical, text, and date and time data type categories in detail. We’ll go through their syntax, storage size, and typical use cases. Read more 7 Jul 2021 Martyna Sławińska What Is the Difference Between a Primary Key and a Unique Key? When designing a database, we often need to decide between defining a primary key vs. a unique key. Both of them are crucial during the design and further phases of a database. They allow us to uniquely identify each row, ensure the uniqueness of values in the column(s), and more. Let’s take a deep dive to learn more. This article will go through the primary and unique keys, their functions, and features. Read more 18 Jun 2021 Martyna Sławińska An Overview of PostgreSQL Data Types It’s vital to know what you actually store in your database. That’s why every column has its data type. There are numerous PostgreSQL data types across various categories. Read on to see which data type suits which use case! In this article, we’ll go through the most common data types used in PostgreSQL. PostgreSQL, also called Postgres, is a well-known open-source object-relational database management system (DBMS). It is SQL-compliant, extensible, and includes all standard relational database features, such as database constraints, transactions, views, triggers, stored procedures, and more. Read more 20 May 2021 Martyna Sławińska What’s the Difference Between UNIQUE and DISTINCT in SQL? We use the words unique and distinct interchangeably in our day-to-day life. However, these words play very different roles in SQL. Let’s find out what is so different about them and how we can use them in SQL. Despite the words unique and distinct being synonyms, they cover very different things in SQL. The UNIQUE keyword in SQL plays the role of a database constraint; it ensures there are no duplicate values stored in a particular column or a set of columns. Read more 27 Apr 2021 Martyna Sławińska What Is the Benefit of Foreign Keys in SQL? What is a foreign key and why is it so important in relational databases? Learn all the details about foreign keys in this article. One of relational databases’ key features is the ability to link data stored in different tables. These links, called references, essentially act as connections between tables. They are created using the FOREIGN KEY constraint on table columns. In this article, we’ll learn what the FOREIGN KEY constraint does in SQL. Read more «« « 1 2 » »»