Question

I save user inputs (comments) in these tables.

NEWS_COMMENTS
- id
- comment

PRODUCT_COMMENTS
- id
- comment
- product_id

I wanted to add a history feature to my website. Like;

-Someone commented on XX news.
-Someone commented on YY product.
-Someone commented on ZZ product.

You noticed the issue. I don’t save timestamps or dates, so I can’t be sure which comment comes first. It can be either the news comment or product comment.

Does MySQL has a feature to select last 24 hour inputs? For example,

NEWS_COMMENTS has 3 new entries in last 24 hours.
PRODUCT_COMMENTS has 5 new entries in last 24 hours.

The query should select these 8 entries ordering by their entry date/timestamp.

Can I do this without altering my current pages? Can you provide a query?

Answer 1

All you need to do is add a column with type timestamp and the option DEFAULT CURRENT_TIMESTAMP. You probably don’t need any other modifications to your code – MySQL will do the magic to ensure that the timestamp is automatically filled in when you insert rows.

• Automatic Initialization and Updating for TIMESTAMP and DATETIME

Then you can get the rows from the last 24 hours with a simple query:

SELECT col1, col2, ..., coln
FROM yourtable
WHERE yourtimestampcol > NOW() - interval 24 hour