I’m developing a web app using PHP and MySQL, and I need to decide how to store date and time data in my database. I’m considering whether to use the datetime or timestamp data types, but I’m unsure which one would be more suitable for my needs.
I understand that both types can hold date and time information, yet they may function differently. Some users recommend timestamp for specific cases, while others vouch for datetime.
Could someone clarify the differences between these two types and guide me on when to use each? What advantages and disadvantages do datetime and timestamp have in MySQL? I want to ensure I make the right choice for my PHP application before I start constructing my database tables.
honestly the 2038 problem with timestamp is gonna bite you eventually if your app lives long enough. datetime doesn’t have that headache and you wont have to migrate later when you hit that wall
i agree, that timestamp can be a pain with timezones! datetime is definitely more stable since it just keeps what you input. unless you’re dealing with a lot of timezone stuff, i’d stick with datetime for clarity.
From my experience building several PHP applications, the choice really depends on your storage requirements and timezone handling needs. TIMESTAMP has a smaller storage footprint (4 bytes vs 8 bytes for DATETIME) which matters when you’re dealing with large datasets. However, TIMESTAMP is limited to the range 1970-2038 due to Unix timestamp limitations, while DATETIME can handle dates from 1000-9999. One thing that caught me off guard initially was that TIMESTAMP automatically converts to UTC for storage and back to your session timezone on retrieval. This can be helpful for global applications but confusing if you’re not expecting it. DATETIME stores exactly what you give it without any timezone conversion. For most web applications, I’ve found DATETIME to be more predictable and easier to work with, especially when you’re not dealing with multiple timezones. The storage difference is usually negligible unless you’re at enterprise scale.
Both data types have their place, but there’s one crucial aspect that often gets overlooked - the automatic updating behavior of TIMESTAMP. By default, TIMESTAMP columns automatically update to the current timestamp when a record is modified, which can be incredibly useful for tracking changes without writing additional code. However, this automatic behavior can also cause unexpected updates if you’re not careful. DATETIME doesn’t have this automatic updating feature, giving you complete control over when values change. Another consideration is MySQL version compatibility - older MySQL versions had different behaviors for these types, so if you’re working with legacy systems, DATETIME tends to be more consistent across versions. In my recent projects, I’ve started using DATETIME for user-facing dates like birthdays or event dates, and TIMESTAMP only for system-generated timestamps like created_at or updated_at fields where I want that automatic updating behavior.