Converting Unix Timestamps to SQL DateTime with Milliseconds in VB.NET

Introduction

When working with databases, it’s common to encounter date and time values stored in different formats. In this article, we’ll explore how to convert a 13-digit Unix timestamp into a SQL DateTime format with milliseconds using VB.NET.

Background on Unix Timestamps

A Unix timestamp is the number of seconds that have elapsed since January 1, 1970, at 00:00:00 UTC (Coordinated Universal Time). This format is used in many systems to represent dates and times. The 13-digit format you’re looking for typically includes milliseconds.

For example, the Unix timestamp 1561476867713 represents a date and time of June 25, 2019, at 4:34:27 PM, with milliseconds.

VB.NET and SQL Server 2016

In this article, we’ll focus on using VB.NET to convert the Unix timestamp into a SQL DateTime format that can be used as a parameter in a SQL query. We’ll also explore how to handle the conversion process accurately and efficiently.

Understanding the Problem

You’ve tried various solutions, but none have worked for your specific situation. You’re working with VB.NET and SQL Server 2016. The issue lies in converting the Unix timestamp into a SQL DateTime format that includes milliseconds.

Here’s an example of how you can’t achieve this:

Dim timeStamp = "1561476867713"
Dim unixConvertedDate As DateTime = New System.DateTime(1970, 1, 1, 0, 0, 0, 0)
unixConvertedDate = unixConvertedDate.AddMilliseconds(timeStamp).AddHours(1)

Console.WriteLine(unixConvertedDate.ToString("yyyy-MM-dd HH:mm:ss.fff"))

This will output 6/25/2019 4:34:27 PM, but you need the format 2019-06-25 16:34:27.713.

Solution Overview

To achieve this, we’ll use a combination of VB.NET’s built-in date and time manipulation functions, along with SQL Server’s DateTime data type. We’ll create a custom function to convert the Unix timestamp into a SQL DateTime format that includes milliseconds.

Here’s an example implementation:

Function ConvertUnixTimestampToSqlDateTime(unixTimestamp As Long) As String
    Dim sqlDateTime As New DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)
    sqlDateTime = sqlDateTime.AddMilliseconds(unixTimestamp)
    ConvertUnixTimestampToSqlDateTime = sqlDateTime.ToString("yyyy-MM-dd HH:mm:ss.fff")
End Function

Using the Custom Function

Now that we have our custom function, let’s see how to use it in your VB.NET code:

Dim timeStamp As Long = 1561476867713
Dim sqlDateTime As String = ConvertUnixTimestampToSqlDateTime(timeStamp)
Console.WriteLine(sqlDateTime) ' Outputs: 2019-06-25 16:34:27.713

Conclusion

Converting Unix timestamps to SQL DateTime formats with milliseconds can be challenging, but it’s achievable using VB.NET and custom functions. By understanding the Unix timestamp format and leveraging VB.NET’s built-in date and time manipulation functions, you can create a robust solution that accurately converts your dates and times.

Additional Tips and Considerations

• When working with databases, always ensure to handle date and time values in a way that accommodates different time zones.
• SQL Server’s DateTime data type is stored as UTC (Coordinated Universal Time), so when converting Unix timestamps to this format, keep this in mind to avoid issues.
• For more advanced date and time operations, explore VB.NET’s DateTimeOffset struct and SQL Server’s date and time functions.

Example Use Case

Suppose you’re building an e-commerce application where users can track orders. You want to display the date and time when an order was placed, but in a format that’s easily understandable by your customers. Using our custom function, you can convert the Unix timestamp into a SQL DateTime format with milliseconds:

Dim unixTimestamp As Long = 1561476867713
Dim sqlDateTime As String = ConvertUnixTimestampToSqlDateTime(unixTimestamp)
Console.WriteLine(sqlDateTime) ' Outputs: 2019-06-25 16:34:27.713

// Displaying the date and time in your UI component
Console.WriteLine("Order placed on " + sqlDateTime)

By converting the Unix timestamp to a SQL DateTime format, you can create a more user-friendly experience for your customers.

Troubleshooting Tips

• When working with custom functions, ensure that they’re correctly implemented and tested.
• Always validate input parameters when using custom functions to avoid potential errors.
• For complex date and time operations, consider exploring SQL Server’s built-in date and time functions or leveraging third-party libraries.

Last modified on 2025-04-10