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SET versus SELECT when assigning variables?
What are the differences between the SET and SELECT statements when assigning variables in T-SQL?
4 Answers
...
How do you debug MySQL stored procedures?
...E debug_msg(enabled INTEGER, msg VARCHAR(255))
BEGIN
IF enabled THEN
select concat('** ', msg) AS '** DEBUG:';
END IF;
END $$
CREATE PROCEDURE test_procedure(arg1 INTEGER, arg2 INTEGER)
BEGIN
SET @enabled = TRUE;
call debug_msg(@enabled, 'my first debug message');
call debug_msg(@ena...
Can overridden methods differ in return type?
... class Alpha {
Alpha doStuff(char c) {
return new Alpha();
}
}
class Beta extends Alpha {
Beta doStuff(char c) { // legal override in Java 1.5
return new Beta...
Set keyboard caret position in html textbox
...tRange();
range.move('character', caretPos);
range.select();
}
else {
if(elem.selectionStart) {
elem.focus();
elem.setSelectionRange(caretPos, caretPos);
}
else
elem.focus();
...
Select Last Row in the Table
I would like to retrieve the last file inserted into my table. I know that the method first() exists and provides you with the first file in the table but I don't know how to get the last insert.
...
Change auto increment starting number?
...foobar(moobar) values ("def");
INSERT INTO foobar(moobar) values ("xyz");
select * from foobar;
'10', 'abc'
'11', 'def'
'12', 'xyz'
This auto increments the id column by one starting at 10.
Auto increment in MySQL by 5, starting at 10:
drop table foobar
create table foobar(
id IN...
How to get the number of days of difference between two dates on mysql?
...lues are
used in the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------...
Android file chooser [closed]
...ent in an Intent.createChooser() like this:
private static final int FILE_SELECT_CODE = 0;
private void showFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
try {
startActivityForR...
What are the uses for Cross Join?
...ly, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might c...
Calculating Distance between two Latitude and Longitude GeoCoordinates
...atic double DistanceTo(double lat1, double lon1, double lat2, double lon2, char unit = 'K')
{
double rlat1 = Math.PI*lat1/180;
double rlat2 = Math.PI*lat2/180;
double theta = lon1 - lon2;
double rtheta = Math.PI*theta/180;
double dist =
Math.Sin(rlat1)*Math.Sin(rlat2) + M...