在$ sql查询中使用date（）进行过滤

Question

I'm having problems understanding where to place the conversion to take the unixtime and convert it to the specific month and year.

$sql = "SELECT * FROM logs WHERE clientid = '5604' AND timestamp = 'Jan 13' ";

Where would I need to place the date() function to filter the timestamp to month and year specified?

Answer 1

First of all, date litterals in MySQL must follow one of the below formats:

• YY*MM*DD
• YYYY*MM*DD

* means "any non-digit non-alphanumeric character or no character at all".

YY or YYYY is the year with two or four digits.

MM and DD are the month and day numbers.

Then, if you want to get results for a specific date, you can do something like this:

... WHERE DATE(timestamp_field) = '2013-01-13';

But actually this query wouldn't be able to use an index on timestamp_field . This approach is better because and index on timestamp_field could be used:

... WHERE timestamp_field >= '2013-01-13' AND timestamp_field < '2013-01-14';

Answer 2

Create two variables. Make 1 equal to the 1st day of the year month you want and the 2nd equal to the 1st day of the following year month. Then it's simply this:

where timestamp >= your first variable
and timestamp < your second variable

This approach will handle the time component of your timestamp field and will perform faster than if you try to use functions.