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Learn how to generate a timestamp in Oracle that maintains today's date with a fixed time, such as 09:00:00. This guide breaks down the solutions and offers easy-to-follow examples.
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How to Create a Fixed Time Stamp in Oracle

When working with date and time in Oracle, you might encounter situations where you're required to generate a timestamp reflecting the current date but with a specific, unchanging time. For example, you may need a timestamp that showcases today's date with a constant time of 09:00:00. This is a common requirement in database operations, reporting, and scheduling tasks.

In this guide, we will explore the steps to achieve a fixed time stamp in Oracle, similar to how it can be done in other database systems like MSSQL. We will cover the Oracle syntax you can use to generate this timestamp easily.

Understanding the Requirement

To clarify, here’s what we want to achieve:

Today’s Date: Automatically retrieved from the system date.

Fixed Time: Always set to 09:00:00.

For instance, if today’s date is October 20, 2020, the desired output should be:

[[See Video to Reveal this Text or Code Snippet]]

The Oracle Solution

Using TRUNC with INTERVAL

Assuming you want a date rather than a varchar2, one of the most effective ways to create a fixed timestamp in Oracle is as follows:

[[See Video to Reveal this Text or Code Snippet]]

Breakdown of the Code:

trunc(sysdate): This function is used to round down the current date and time to midnight, giving you the base date without any time component (00:00:00).

interval '9' hour: This expression adds 9 hours to the midnight time produced by trunc(sysdate), resulting in the desired fixed time of 09:00:00.

Alternative Approach: Adding Fraction of a Day

You can also achieve the same result by adding a fraction of a day to trunc(sysdate). Here’s how you do it:

[[See Video to Reveal this Text or Code Snippet]]

Explanation:

9/24: In the context of dates, adding 1 represents a full day. Hence, adding 9/24 effectively adds 9 hours to the midnight timestamp.

Why Use INTERVAL Notation?

If you're coming from a programming background that doesn't use Oracle, you might find the interval notation to be more intuitive and self-explanatory compared to working with fractions of a day. It clearly indicates that you're adding a specific time interval rather than performing a mathematical operation on a date value.

Conclusion

Creating a timestamp with a fixed time part in Oracle is straightforward once you understand the functions involved. By using either the trunc function combined with interval or adding fractions of a day, you can achieve this easily. These techniques can be extremely useful in generating meaningful timestamps that align with your application's need for consistency in time representation.

Now you can confidently generate timestamps that always reflect a constant time representation while still being dynamic to the current date. Don't hesitate to try this out in your Oracle environment today!