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mysql - how many columns is too many?
...every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name the columns you need.
As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entit...
Getting jQuery to recognise .change() in IE
..., in my testing this is not correct and jquery's click does trigger when i select the next radio button using arrow keys. (vista, ie7)
– svandragt
Nov 7 '08 at 13:51
1
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Can you grab or delete between parentheses in vi/vim?
...motion commands by entering :help various-motions in command mode.
object-select
There is another set of motion commands that you can use in Visual mode to select various text objects.
To solve your specific problem you would do the following:
printf("%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32...
Landscape printing from HTML
...y seem to work in IE7 but this is because IE7 will remember the users last selection of landscape or portrait in print preview (only the browser is re-started).
This article does have some suggested work arounds using JavaScript or ActiveX that send keys to the users browser although it they are no...
What does the “~” (tilde/squiggle/twiddle) CSS selector mean?
...
The ~ selector is in fact the General sibling combinator (renamed to Subsequent-sibling combinator in selectors Level 4):
The general sibling combinator is made of the "tilde" (U+007E, ~)
character that separates two sequence...
Visual Studio opens the default browser instead of Internet Explorer
...er:
1) Right click on a .aspx page in your
solution explorer
2) Select the "browse with" context
menu option
3) In the dialog you can select or add
a browser. If you want Firefox in the
list, click "add" and point to the
firefox.exe filename
4) Click the "Set as Default...
Disable firefox same origin policy
...act the zip, get inside the "cors-everywhere-firefox-addon-master" folder, select all the items and zip them.
Then, rename the created zip as *.xpi
Note: If you are using the OS X gui, it may create some hidden files, so you 'd be better using the command line.
3) Installing the xpi
You can just ...
How do I extract a sub-hash from a hash?
...e same:
h1 = {:a => :A, :b => :B, :c => :C, :d => :D}
h2 = h1.select {|key, value| [:b, :d, :e, :f].include?(key) } # => {:b=>:B, :d=>:D}
h1 = Hash[h1.to_a - h2.to_a] # => {:a=>:A, :c=>:C}
And if you want to patch that into the Hash class:
class Hash
def extract...
Simplest way to profile a PHP script
...connect_to_db();
prof_flag("Perform query");
// Get all the data
$select_query = "SELECT * FROM data_table";
$result = mysql_query($select_query);
prof_flag("Retrieve data");
$rows = array();
$found_data=false;
while($r = mysql_fetch_assoc($result))
{
$found_data=tru...
Is there a way to rename an Xcode 4 scheme?
... hit "Manage Schemes". Once you do so, you'll have a window like this:
Select the scheme you want to change, and hit Return.
Now the scheme name will be editable, and you can change it to your hearts desire. Then hit Return again to save it.
...