Next up on our MySQL to-do list is to learn about storing dates and times. There are various data types in MySQL for storing dates and times. It seems MySQL and databases likes to break everything up into multiple data types to make things more organized at the consequence of being confusing and annoying.
This video is going to be talking about the DATETIME, DATE, and TIME data types. These are all used to store, you guessed it, dates and times. The one you choose depends on your needs. If you just need dates, choose DATE. If you just need times, choose TIME, if you need both stored together, choose DATETIME.
Now you set a column one of these data types whenever you want every row for this field to have some sort of date, time or both…but how exactly is the data formatted? This requires us to understand some convention. For example, in the USA at least, if you have something like 4:30AM, by convention you know the hour is 4 and the minutes are 30. But this is just an agreed upon convention. MySQL has its own convention…For example 2017-02-02. The first thing is the year, the second is the month, and the third is the day. That is for the DATE. The convention for time is 22:54:30. The first is the hour (military time), the second is the minute, and the third is the seconds. Lastly, there can actually be fractions of seconds…up to microseconds! .123456. To use fractional seconds though you must specify to MySQL the precision of the TIME or DATETIME when you create it, for example DATETIME(6) would allow microsecond precision.
How do you actually give a date to MySQL? By that I mean let’s say you have a table with a column of DATETIME(6), and you want to give a value for that column, how do you format it? It’s quoted. For example:
MySQL interprets this as a DATETIME.
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