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Throw an error in a MySQL trigger
...e SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a more complete example of the approach:
delimiter //
use test//
create table trigger_test
(
id int...
Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...answer so I don't want to add another. He could also use list.append to really put his mind at ease. docs.python.org/2/tutorial/datastructures.html
– NG.
Dec 4 '12 at 0:15
1
...
Entity Framework 6 Code first Default value
...
You can do it by manually edit code first migration:
public override void Up()
{
AddColumn("dbo.Events", "Active", c => c.Boolean(nullable: false, defaultValue: true));
}
...
How to convert image to byte array
...ollows:
public static byte[] converterDemo(Image x)
{
ImageConverter _imageConverter = new ImageConverter();
byte[] xByte = (byte[])_imageConverter.ConvertTo(x, typeof(byte[]));
return xByte;
}
share
...
How to change height of grouped UITableView header?
...
Return CGFLOAT_MIN instead of 0 for your desired section height.
Returning 0 causes UITableView to use a default value. This is
undocumented behavior. If you return a very small number, you
effectively get a zero-height header.
S...
Auto Resize Image in CSS FlexBox Layout and keeping Aspect Ratio?
... it also possible to do this for the height dimension if the screen gets smaller?
– confile
Jan 14 '14 at 0:43
@confil...
How to create a date object from string in javascript [duplicate]
...return a JS Date object, with a robust selection of methods available from __proto__. Demo in jsFiddle
– KyleMit
Apr 11 '17 at 19:19
4
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Where is array's length property defined?
...uage itself.
10.7. Array Members
The members of an array type are all of the following:
The public final field length, which contains the number of components of the array. length may be positive or zero.
The public method clone, which overrides the method of the same name in clas...
How do I insert NULL values using PDO?
...akes a variable, to reference, and doesn't pull in a value at the time of calling bindParam. I found this in a comment on the php docs:
bindValue(':param', null, PDO::PARAM_INT);
EDIT: P.S. You may be tempted to do this bindValue(':param', null, PDO::PARAM_NULL); but it did not work for everybody...
MySQL get the date n days ago as a timestamp
...
DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT U...