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Introduction The compatibility level of a database is important because it determines which features are available and can also affect the performance of queries and other operations in the database. For example, if a database has a compatibility level of 100 (SQL Server 2008), certain features that were introduced in later versions of SQL Server, such as memory-optimized tables or table variables with large record sizes, will not be available for use in that database. It is important to set the compatibility level of a database to the correct level, as changing the compatibility level of a database can cause ... Read More
Introduction To rename a schema in SQL Server, you can use the sp_rename stored procedure to change the name of the schema. Before you can rename a schema, you need to make sure that the schema is not being used by any objects in the database. You can do this by running a query to check for objects that belong to the schema. If the schema is being used by objects in the database, you will need to either drop or transfer ownership of the objects to a different schema before you can rename the schema. Once you have ... Read More
Introduction If you have a table in MySQL with a BLOB field that you would like to convert to a JSON field, it can be done by performing a series of ALTER TABLE statements. The process involves creating a new column with the desired data type (JSON), copying the data from the old column to the new column, dropping the old column, and renaming the new column to the original column name. It's important to note that BLOB fields are used to store binary data, and JSON is a text-based format for representing data. In order to convert a BLOB ... Read More
Introduction In SQL Server, a schema is a container for database objects such as tables, views, and stored procedures. The `dbo` schema is the default schema for the database owner (also known as the "database principal"). There may be times when you want to change the schema of a database object in SQL Server. For example, you might want to move a table from one schema to another to better organize your database, or you might want to change the schema of an object to match the schema of other objects in your database. To change the schema of a ... Read More
Introduction A Linux zombie process is a process that has completed execution, but its parent process has not yet collected its exit status. These processes can cause system slowdowns and memory leaks if left unaddressed. In this article, we will discuss how to clean up a Linux zombie process and prevent them from occurring in the future. Checking for Zombies In order to check for zombies, you can use the command "ps aux | grep Z" in the terminal. This command will display all processes that are in the zombies state, showing the process ID (PID), the parent process ID ... Read More
Root-login over SSH is a common method for gaining access to a Linux server, but it is not always the most secure option. In this article, we will explore the reasons why disabling root-login over SSH is a good idea, and provide examples of how to do so. What is Root-Login Over SSH? When a Linux server is set up, the root user is created by default. The root user is the most powerful user on the system, and has the ability to perform any task, including making changes to the system configuration, installing software, and creating new users. When ... Read More
Introduction Displaying employees in increasing order of their salaries in SQL Server involves a few steps. First, you need to have a database and a table that stores information about employees, including their salaries. Once you have that, you can use SQL commands to query the table and retrieve the data in the desired order. To retrieve the data in increasing order of salary, you can use the ORDER BY clause in a SELECT statement. The ORDER BY clause is used to sort the results of a query by one or more columns. In this case, you would use it ... Read More
Creating a crontab through a script on Linux is a simple and efficient way to automate repetitive tasks and schedule them to run at specific intervals. In this article, we will take a closer look at how to create a crontab through a script on Linux, including examples and tips for troubleshooting. What is a Crontab? A crontab is a Linux feature that allows users to schedule tasks to run automatically at specific intervals. This can be useful for tasks such as running backups, sending email reminders, or performing maintenance tasks. The crontab is controlled by a daemon called cron, ... Read More
When working with the command line on a Unix or Linux operating system, there are three files that play an important role in setting up and configuring your shell environment: .bashrc, .bash_profile, and .profile. These files are used to customize your shell environment and set up different settings and configurations depending on your needs. In this article, we will take a closer look at each of these files and explore the differences between them, including examples of how they can be used to customize your shell environment. Bashrc The .bashrc file is a configuration file that is used to set ... Read More
Introduction Displaying the department with the most number of employees in SQL Server is a common task that can be accomplished using a SQL query. The query will typically involve joining the employees and departments tables on the department ID, grouping the results by department name, and counting the number of employees in each department. Then use aggregate functions like COUNT() and TOP 1 with ORDER BY clause to get the desired result. To display the department name that has the most number of employees in SQL Server, it requires to have two database tables - Employees and Departments with ... Read More