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How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
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How to redirect the output of a PowerShell to a file during its execution
...put to a file. The problem is that I cannot change the way this script is called. So I cannot do:
10 Answers
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Why should we typedef a struct so often in C?
...As Greg Hewgill said, the typedef means you no longer have to write struct all over the place. That not only saves keystrokes, it also can make the code cleaner since it provides a smidgen more abstraction.
Stuff like
typedef struct {
int x, y;
} Point;
Point point_new(int x, int y)
{
Point a...
Where to use EJB 3.1 and CDI?
... together.
EJB >= CDI
Note that EJBs are CDI beans and therefore have all the benefits of CDI. The reverse is not true (yet). So definitely don't get into the habit of thinking "EJB vs CDI" as that logic really translates to "EJB+CDI vs CDI", which is an odd equation.
In future versions of J...
Take diff of two vertical opened windows in Vim
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To begin diffing on all visible windows:
:windo diffthis
which executes :diffthis on each window.
To end diff mode:
:diffoff!
(The ! makes diffoff apply to all windows of the current tab - it'd be nice if diffthis had the same feature, bu...
MySQL: multiple tables or one table with many columns?
...elational database to minimize redundancy and dependency. Normalization usually involves dividing large tables into smaller (and less redundant) tables and defining relationships between them. The objective is to isolate data so that additions, deletions, and modifications of a field can be made in ...
What's the Point of Multiple Redis Databases?
...ce are no different than schemas in RDBMS database instances.
So, with all of that said, why/when would I ever want to use multiple
Redis databases instead of just spinning up an extra instance of Redis
for each extra database I want?
There's one clear advantage of using redis databases in...
How to allow only one radio button to be checked?
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OMG... well, if I dont assign names to them. they all should have empty string as name by default right? Thank you
– Clinteney Hui
Mar 24 '11 at 12:58
20
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Make div stay at bottom of page's content all the time even when there are scrollbars
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@aroth that is because they are two totally different solutions. This solution will keep the footer at the bottom of the visual area of the screen at all times. The alternative solution keeps the footer at either the bottom of the screen or the bottom of the page,...
Is there a “previous sibling” selector?
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I found a way to style all previous siblings (opposite of ~) that may work depending on what you need.
Let's say you have a list of links and when hovering on one, all the previous ones should turn red. You can do it like this:
/* default lin...