Insert time minus one hour

[slanoss]

I insert a time value using the following code

 

 

$ti= ( !empty($_POST['time']) ) ? "'{$_POST['time']}'" : 'NULL'; 

 

I want to insert a second time value into a differen column which would be the same time minus 1 hour

 

something along the lines of :

 

$ti2= ( !empty($_POST['time']) ) ? "'{$_POST['time'] -1 hour}'" : 'NULL'; 

 

What would be the correct way to do it

[Barand]

INSERT INTO tablename (col1, col2) VALUES ('$t1', '$t1' - INTERVAL 1 HOUR)

[slanoss]

In my original I have

Insert into table1 (time) values ($ti);

which works correctly (no quotes round $ti)

 

I have put 

insert into table1 (time, time2) values ($ti, $ti - interval 1 hour );

But it doesn't work, NULL is inserted into time2 not time minus 1 hour

 

Any ideas , thanks.

[Barand]

So your your times are not in TIME format then?

 

What format are they?

[Barand]

Looks like INTERVAL works only on  DATETIME and not TIME columns, so needs SUBTIME()

 

INSERT INTO test (timecol1, timecol2) VALUES ('03:00', SUBTIME('03:00', '1:00'));