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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...ables, with a single column each, and data as follows:
A B
- -
1 3
2 4
3 5
4 6
Note that (1,2) are unique to A, (3,4) are common, and (5,6) are unique to B.
Inner join
An inner join using either of the equivalent queries gives the intersection of the two tables, i.e. the two r...
NSObject +load and +initialize - What do they do?
... return 0;
}
This program prints two lines of output:
2012-11-10 16:18:38.984 testApp[7498:c07] in Superclass initialize; self = Superclass
2012-11-10 16:18:38.987 testApp[7498:c07] in Superclass initialize; self = Subclass
Since the system sends the initialize method lazily, a class won't rec...
Can you explain the HttpURLConnection connection process?
... connection. This is data that you are sending
// to the server
// 3. No. Sending the data is conducted here. We established the
// connection with getOutputStream
writer.write("message=" + message);
// Closes this output stream and releases any system resources
// associate...
How to determine the longest increasing subsequence using dynamic programming?
...N) = O(N log N)
Now let's do a real example:
Collection of integers:
2 6 3 4 1 2 9 5 8
Steps:
0. S = {} - Initialize S to the empty set
1. S = {2} - New largest LIS
2. S = {2, 6} - New largest LIS
3. S = {2, 3} - Changed 6 to 3
4. S = {2, 3, 4} - New largest LIS
5. S = {1, 3, 4} - Changed 2 to 1...
Flexbox and Internet Explorer 11 (display:flex in ?)
...
153
According to http://caniuse.com/#feat=flexbox:
"IE10 and IE11 default values for flex are 0 0 a...
Why exactly is eval evil?
...tors:
(let ((ops '(+ *)))
(dolist (op ops)
(print (eval (list op 1 2 3)))))
That's better written as:
(let ((ops '(+ *)))
(dolist (op ops)
(print (funcall op 1 2 3))))
There are lots of examples where beginners learning Lisp think they need EVAL, but they don't need it - since expressi...
Proper way to use AJAX Post in jquery to pass model from strongly typed MVC3 view
... my "jargon" is not correct.
I've got a project using ASP.NET using the MVC3 framework.
5 Answers
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Delete the first three rows of a dataframe in pandas
...
Use iloc:
df = df.iloc[3:]
will give you a new df without the first three rows.
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Entity Framework 4 / POCO - Where to start? [closed]
...ogs.msdn.com/b/adonet/archive/2009/06/10/poco-in-the-entity-framework-part-3-change-tracking-with-poco.aspx
In these articles the author mentions future articles that describe best practices in implementing Repository and Unit of Work patterns, but I can't find them. These articles are well writte...
How can I trim leading and trailing white space?
...
13 Answers
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