SELECT statement with date expression
am 04.02.2006 02:12:11 von zMisc
I got a table with the following fields:
BirthDay (Date)
Reminder (Short integer)
I need to select all records where BirthDay - Reminder <= Today to display a
reminder.
In Access and MS SQL, I can do this:
SELECT ..... WHERE BirthDay - Reminder <= 01/01/2006
assuming 01/01/2006 is today's date.
Access and MS SQL can substract a number (Reminder) from BirthDay.
Can someone please tell me how I can achieve the same SELECT in MySQL?
Any help greatly appreciated.
Tks
John
Re: SELECT statement with date expression
am 04.02.2006 10:18:41 von Aggro
zMisc wrote:
> I got a table with the following fields:
>
> BirthDay (Date)
> Reminder (Short integer)
>
> I need to select all records where BirthDay - Reminder <= Today to display a
> reminder.
>
> In Access and MS SQL, I can do this:
>
> SELECT ..... WHERE BirthDay - Reminder <= 01/01/2006
>
> assuming 01/01/2006 is today's date.
First you need to convert that string into correct date format
yyyy-mm-dd so it would be 2006-01-01.
Then you need '' characters around the date '2006-01-01'
But if you are really using the current date, you can use curdate()
function instead of the '2006-01-01' to get the current date.
Then see the first example in this page how to subtract certain amount
of days (or other units) from a date:
http://dev.mysql.com/doc/refman/5.0/en/date-and-time-functio ns.html
Re: SELECT statement with date expression
am 04.02.2006 22:20:31 von Bill Karwin
"zMisc" wrote in message
news:LbTEf.235724$V7.101323@news-server.bigpond.net.au...
> Access and MS SQL can substract a number (Reminder) from BirthDay.
>
> Can someone please tell me how I can achieve the same SELECT in MySQL?
Read about the functions DATE_ADD() and DATE_SUB() on this page:
http://dev.mysql.com/doc/refman/5.0/en/date-and-time-functio ns.html
MySQL also supports ANSI SQL syntax for date arithmetic, for example:
WHERE BirthDay - INTERVAL Reminder DAY <= '2006-01-01'
Note that MySQL date constants are strings, so must be in single-quotes, and
they must be in YYYY-MM-DD format.
Regards,
Bill K.