Category: SQL

In SQL Server, the ALTER command is a powerful tool for modifying existing tables and columns in your database without needing to delete or recreate them. One of the most common uses of this command is to change the data type of a column. This can be essential when dealing with evolving business requirements, where…(Continue Reading)

Finding duplicate data is a common task when working with SQL databases, especially in large datasets where unique entries are required. In SQL Server, a well-constructed query can help detect and handle duplicates efficiently. This article will cover the fundamental concepts and SQL techniques for identifying duplicates, explain various query approaches, and offer insights into…(Continue Reading)

DATETIMEOFFSET is a data type in Microsoft SQL Server that stores date and time values along with a time zone offset. This is particularly useful in applications where you need to account for different time zones or when it’s essential to track the time with an offset from UTC. Unlike the standard DATETIME type, which…(Continue Reading)

The SMALLDATETIME data type in SQL Server is used to store date and time values but with a limited range and precision. It provides a compact way to store date and time information when high precision isn’t required, and it occupies less storage than other datetime types, such as DATETIME. Key Features Storage Size: SMALLDATETIME…(Continue Reading)

Comparing dates in SQL Server is a fundamental task, often essential for filtering records by date ranges, checking if dates match specific criteria, or analyzing date-based trends. In SQL Server, there are several methods and functions available to compare dates, offering flexibility depending on the requirements. This guide covers key concepts and practical methods to…(Continue Reading)

An UPDATE statement in SQL Server is used to modify existing records in a table. You can update specific columns of a table with new values based on certain conditions. Here is the general syntax of the UPDATE query: UPDATE table_name SET column1 = value1, column2 = value2, … WHERE condition; Key Components UPDATE table_name:…(Continue Reading)

In SQL Server, concatenation refers to the process of joining two or more strings together to create a single string. This is typically achieved using the + operator or the CONCAT function, depending on the version of SQL Server and the specific use case. Using the + Operator The + operator is a simple way…(Continue Reading)

The EOMONTH function in SQL Server is used to return the last day of the month for a given date. This function is particularly useful when working with date-based calculations, such as determining the end of a reporting period or the last day of the current or previous months. Syntax EOMONTH(start_date [, month_to_add]) start_date: The…(Continue Reading)

In SQL Server, there is no direct WEEKDAY() function like in some other database systems. However, you can use the DATENAME or DATEPART function along with DATEADD or GETDATE to extract the weekday or day of the week from a date. Here are two common ways to achieve this: 1. Using DATEPART(): DATEPART returns the…(Continue Reading)

To get the first day of the month in SQL Server, you can use several methods depending on the version of SQL Server you are working with. Below are a few common approaches: 1. Using the DATEFROMPARTS function The DATEFROMPARTS function allows you to construct a date using the year, month, and day parts. SELECT…(Continue Reading)