How to Convert DateString to int8 in PostgreSQL

Details

Description

Learn how to convert a date string into an `int8` in PostgreSQL efficiently. This guide walks you through the steps to understand and convert to UNIX timestamps for compatible integer values.
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How to Convert DateString to int8 in PostgreSQL: A Complete Guide

In PostgreSQL, sometimes we need to convert a date string into an integer format for various applications, such as filtering or performing calculations. One common representation for dates is the UNIX timestamp, which counts the number of seconds that have elapsed since January 1, 1970. This guide will break down how to perform this conversion effectively using a specific date string example.

The Problem: Conversion of Date String to int8

You may come across a scenario where you have a date string formatted as follows:

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

Your goal is to convert this string into an int8 (64-bit integer) in PostgreSQL. This can be tricky, especially if the input string is provided by an external source and cannot be modified.

The Solution: Working with UNIX Timestamps

Instead of attempting to convert the date string directly to int8, we can use the concept of UNIX timestamps. The UNIX timestamp is a straightforward way of representing dates and times as an integer since it counts seconds from a fixed starting point.

Step-by-Step Conversion

Extract the Timestamp:
To convert the provided date string to an integer, start by extracting the timestamp component. You can achieve this with the following SQL command:

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

Understand the Result:
The output from the above command will be:

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

This integer value 1634579122 represents the total number of seconds that have passed since the beginning of the UNIX epoch (January 1, 1970).

Note: Make sure to replace the date string to match the format without the 'T' and 'Z' characters (for instance, change it to 2021-10-18 17:45:22).

Creating the Full Query

Now, if you need to integrate this query into a larger operation, here's how it can look:

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

This query will give you a UNIX timestamp, which can be stored as an int8.

Conclusion

By following the steps above, you can successfully convert any date string in the format YYYY-MM-DDTHH:MM:SSZ to an integer in PostgreSQL using UNIX timestamps. This method is efficient and reliable, especially when dealing with data coming from external sources where string formats cannot be altered.

Feel free to experiment with different date strings, keeping the format in mind, and enjoy the benefits of simplified date-time handling in your PostgreSQL databases!