CURRENT_DATE() with DATETIME

How do grab entries from yesterday...

[wfernley]

Hey everyone,

I'm still fairly new to MySQL's DATETIME.

I have a table that records conversions for the day. With the entries it records the DATETIME of the conversion with the NOW() function. The date looks like this : 2006-01-26 10:43:51

What is the SQL for grabbing entries from yesterday?
Currently I am trying:
SELECT * FROM conversions WHERE date = CURRENT_DATE() - 1

The SQL query returns nothing with no error even though there are conversions yesterday.

Can anyone help?

Thanks in advance for your replies!

Wes

[Demaestro]

You want

SELECT * FROM conversions WHERE date = CURRENT_DATE() - INTERVAL 1 DAY;

There are other arguments you can do with this, some examples:

SELECT now() + INTERVAL 1 SECOND;

SELECT now() - INTERVAL 1 SECOND;

SELECT now() - INTERVAL 1 MONTH;

SELECT now() - INTERVAL 1 YEAR;

I will sticky you the mysql help page for this, not sure the forum moderator will want the link posted

[coopster]

MySQL is an authoritative site so it is OK to link there.

[dev.mysql.com...]

[wfernley]

Thank you for your replies and link to the MySQL page on Date/Timestamp.

Using SELECT * FROM conversions WHERE date = CURRENT_DATE() - INTERVAL 1 DAY; does not work :S

Just like the other SQL query I mentioned, it says there are no entries from yesterday. Should I work around it using the PGP date function? I know how I can do that but I wanted to get the MySQL date working because its something new ;)

Any other suggestions?

Thanks again!

Wes

[Demaestro]

The problem may be the fact that there are times on your dat so it doesn't match yeterday.

Try this

SELECT
*
FROM
conversions
WHERE
date >= CURRENT_DATE():00:00:00 - INTERVAL 1 DAY
and date <= CURRENT_DATE():12:59:59 - INTERVAL 1 DAY;

The syntax may be off but the basic idea is you want to see if your dateTime falls in the time range for yesterday. There may be a CURRENT_DATE().earliestTime() or CURRENT_DATE().latestTime() funtion that will return the latet and erliest times of a day but I am not sure.

[wfernley]

Thank you Demaestro.

I will try that out. I just got it working but I cheaped out and made two cells, date and time. It's working now but I'm having to use an extra cell.

[Demaestro]

It is cheap but it'll work.

It will suck for ordering by date and time though if they are seperate fields. It will also make comparisons harder if you split them. Like when you want to query things that come before or after something else based on date and time. Because if it has to consider the time then it is a little bit of a hassle. You have to make sure the date fields are equal, then you can check if the time is before or after a time you need to compare against.

Just a heads up of a few pit falls of splitting your datetime field into 2 seperate fields.

[wfernley]

Yeah I understand that ;)

I think they only ordering I will have to do will be simple ordering so it should be alright using the two seperate fields

Thanks again for your help!

[Demaestro]

No problem. I am happy to help with any SQL questions the geek in me loves it.

[Radek_Cvek]

Today:
SELECT * FROM conversions WHERE DAY( date ) = EXTRACT(DAY FROM NOW() )

Yesterday:
SELECT * FROM conversions WHERE DAY( date ) = EXTRACT(DAY FROM (NOW() - INTERVAL
1 DAY ) )