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What's the difference between KeyDown and KeyPress in .NET?
...ctical difference between KeyDown and KeyPress is that KeyPress relays the character resulting from a keypress, and is only called if there is one.
In other words, if you press A on your keyboard, you'll get this sequence of events:
KeyDown: KeyCode=Keys.A, KeyData=Keys.A, Modifiers=Keys.None
Key...
How to call a PHP function on the click of a button
..."insert" value="insert" />
<input type="submit" class="button" name="select" value="select" />
jQuery:
$(document).ready(function(){
$('.button').click(function(){
var clickBtnValue = $(this).val();
var ajaxurl = 'ajax.php',
data = {'action': clickBtnValu...
How do I change tab size in Vim?
...hat's what would happen should tabs be used, rather than always delete one char at a time).
To make a fully educated decision as to how to set things up, you'll need to read Vim docs on tabstop, shiftwidth, softtabstop and expandtab. The most interesting bit is found under expandtab (:help 'expandta...
How to best display in Terminal a MySQL SELECT returning too many fields?
...
Terminate the query with \G in place of ;. For example:
SELECT * FROM sometable\G
This query displays the rows vertically, like this:
*************************** 1. row ***************************
Host: localhost
Db: mydatabase1
...
SQL Switch/Case in 'where' clause
...
declare @locationType varchar(50);
declare @locationID int;
SELECT column1, column2
FROM viewWhatever
WHERE
@locationID =
CASE @locationType
WHEN 'location' THEN account_location
WHEN 'area' THEN xxx_location_area
WHEN 'division' THEN xxx_location_division
END...
Remove the cell highlight color of UITableView
I want to remove the default blue color of uitableview cell selection. I don't want any selection color there. I have not created a custom cell class. I'm customizing the cell by adding labels and buttons over it.
I tried doing:
...
Counting null and non-null values in a single query
...le and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us;
...
jQuery removing '-' character from string
I have a string "-123445". Is it possible to remove the '-' character from the string?
3 Answers
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How to copy a row and insert in same table with a autoincrement field in MySQL?
...
Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSER...
MySQL: selecting rows where a column is null
I'm having a problem where when I try to select the rows that have a NULL for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows.
...