Understanding SQL Server datetime2 for Dev

Welcome to this article, Dev! In this article, we will be discussing SQL Server datetime2 and its importance in SQL Server. We will explore the different aspects of datetime2, its properties, functions, and how it can be used to improve performance in your SQL Server database. So, sit back, relax, and let’s dive into the world of SQL Server datetime2.

What is datetime2?

Datetime2 is a data type in SQL Server that is used to store a combination of date and time values. It was introduced in SQL Server 2008 as an extension to the datetime data type. Datetime2 has a higher precision than datetime and can store date and time values from January 1, 1753, to December 31, 9999.

Datetime2 is defined by using the format datetime2(p), where p represents the fractional seconds precision. The range of the p value is from 0 to 7, with a default value of 7. This means that datetime2 can store date and time values up to a precision of 100 nanoseconds.

Datetime2 Properties

Some of the properties of datetime2 are:

Working with Datetime2

Datetime2 can be used in many ways in SQL Server. Let’s explore some of the ways it can be used.

Inserting Datetime2 Values

To insert datetime2 values, you can use the following format:

INSERT INTO table_name (column1, column2, ..., columnN)VALUES (value1, value2, ..., valueN);

The values must be in the format ‘YYYY-MM-DD hh:mm:ss.fffffffff’, where the f represents the fractional seconds precision.

Selecting Datetime2 Values

To select datetime2 values, you can use the following format:

SELECT column1, column2, ..., columnNFROM table_nameWHERE condition;

The datetime2 values will be returned in the format ‘YYYY-MM-DD hh:mm:ss.fffffffff’.

Using Functions with Datetime2

SQL Server has many built-in functions that can be used with datetime2 values. Let’s explore some of the functions that can be used with datetime2.

DATEADD

The DATEADD function can be used to add or subtract a specified time interval to a datetime2 value. The syntax of the function is as follows:

DATEADD(interval, number, datetime2_expression)

The interval can be one of the following values: year, quarter, month, day, week, hour, minute, second, millisecond, microsecond, or nanosecond.

DATEDIFF

The DATEDIFF function can be used to calculate the difference between two datetime2 values. The syntax of the function is as follows:

DATEDIFF(interval, start_datetime2, end_datetime2)

The interval can be one of the following values: year, quarter, month, day, week, hour, minute, second, millisecond, microsecond, or nanosecond.

GETDATE

The GETDATE function can be used to return the current datetime2 value of the system. The syntax of the function is as follows:

GETDATE()

Datetime2 and Performance

Datetime2 can be used to improve performance in your SQL Server database. One way to do this is by using datetime2 instead of datetime, as datetime2 has a higher precision and can store more accurate date and time values. This can be useful when dealing with data that requires a high level of accuracy, such as financial data.

Another way to improve performance is by using datetime2 instead of string values when dealing with date and time values. This is because datetime2 values can be indexed, which can help improve query performance.

Frequently Asked Questions

What is the difference between datetime and datetime2?

Datetime2 has a higher precision than datetime and can store date and time values up to a precision of 100 nanoseconds. Datetime can store date and time values up to a precision of 3.33 milliseconds.

Can datetime2 values be indexed?

Yes, datetime2 values can be indexed, which can help improve query performance.

What is the default precision of datetime2?

The default precision of datetime2 is 7.

What is the range of datetime2 values?

Datetime2 can store date and time values from January 1, 1753, to December 31, 9999.

What is the storage size of datetime2?

The storage size of datetime2 is 6-8 bytes, depending on the precision.

Conclusion

So, there you have it, Dev. A comprehensive guide to SQL Server datetime2. We have discussed what datetime2 is, its properties, how to work with datetime2, and how it can be used to improve performance in your SQL Server database. We hope that this guide has been informative and has provided you with the knowledge you need to use datetime2 effectively in your SQL Server environment.