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SQL JOIN - WHERE clause vs. ON clause
...der and its lines, if any, for order number 12345. The second will return all orders, but only order 12345 will have any lines associated with it.
With an INNER JOIN, the clauses are effectively equivalent. However, just because they are functionally the same, in that they produce the same results...
Which is the best library for XML parsing in java [closed]
...
Actually Java supports 4 methods to parse XML out of the box:
DOM Parser/Builder: The whole XML structure is loaded into memory and you can use the well known DOM methods to work with it. DOM also allows you to write to the docu...
Good PHP ORM Library?
...database (it creates everything on the fly)
No models
etc.
It even does all the locking and transactions for you and monitors performance in the background. (Heck! it even does garbage collection....) Best of all... you don't have to write a single... line of code... Jesus this, ORM layer, saved ...
How to remove indentation from an unordered list item?
I want to remove all indentation from ul . I tried setting margin , padding , text-indent to 0 , but no avail. Seems that setting text-indent to a negative number does the trick - but is that really the only way to remove the indentation?
...
what is the difference between OLE DB and ODBC data sources?
...
Actually sometimes OLE DB wraps the ODBC driver, sometimes it doesn't. See here
– bobobobo
Apr 11 '12 at 2:42
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Fatal error: use of unimplemented initializer 'init(coder:)' for class
... is required because instantiating a UIViewController from a UIStoryboard calls it.
To see how we initialize a UIViewController from a UIStoryboard, please take a look here
Why is this not a problem with Objective-C?
Because Objective-C automatically inherits all the required UIViewController initia...
JSF backing bean structure (best practices)
...as defined in the above article by Neil Griffin:
Model Managed-Bean: Normally session scope. This type of managed-bean participates in the "Model" concern of the MVC design pattern. When you see the word "model" -- think DATA. A JSF model-bean should be a POJO that follows the JavaBean design pat...
Python regex find all overlapping matches?
...ead captures the text you're interested in, but the actual match is technically the zero-width substring before the lookahead, so the matches are technically non-overlapping:
import re
s = "123456789123456789"
matches = re.finditer(r'(?=(\d{10}))',s)
results = [int(match.group(1)) for match in mat...
CSS text-overflow in a table cell?
...d flexibility. Also, the containing table will need a specific width, typically width: 100%;, and the columns will typically have their width set as percentage of the total width
table {width: 100%;}
td
{
max-width: 0;
overflow: hidden;
text-overflow: ellipsis;
white-space: nowrap;
}
td.column_a...
Convert a list to a data frame
...hich in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns to factors, to avoid this you can add a parameter to the data.frame() call:
df <- data.frame(matrix(unl...