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Update multiple rows in same query using PostgreSQL
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You can also use update ... from syntax and use a mapping table. If you want to update more than one column, it's much more generalizable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
wher...
Never seen before C++ for loop
... unusual constructs weren't considered the most readable solution possible and may therefore be frowned-upon by some.
– Bill K
Jul 31 '12 at 19:50
2
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Differences between Line and Branch coverage
...comments, conditionals, etc). Branch coverages checks if you took the true and false branch for each conditional (if, while, for). You'll have twice as many branches as conditionals.
Why do you care? Consider the example:
public int getNameLength(boolean isCoolUser) {
User user = null;
if ...
SQL Server: Difference between PARTITION BY and GROUP BY
...A group by normally reduces the number of rows returned by rolling them up and calculating averages or sums for each row. partition by does not affect the number of rows returned, but it changes how a window function's result is calculated.
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How to get a cross-origin resource sharing (CORS) post request working
...has two web servers. The first is the in-built one in XBMC (on port 8080) and displays our library. The second server is a CherryPy python script (port 8081) that I am using to trigger a file conversion on demand. The file conversion is triggered by a AJAX POST request from the page served from t...
Scala: What is the difference between Traversable and Iterable traits in Scala collections?
I have looked at this question but still don't understand the difference between Iterable and Traversable traits. Can someone explain ?
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Is putting a div inside an anchor ever correct?
...<a> element "may be wrapped around entire paragraphs, lists, tables, and so forth, even entire sections, so long as there is no interactive content within (e.g. buttons or other links)".
HTML 4.01 specifies that <a> elements may only contain inline elements. A <div> is a block elem...
Why modelVersion of pom.xml is necessary and always set to 4.0.0?
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It is always set to 4.0.0 in Maven 2 and 3, because, at present, there is no other model.
Notice that modelVersion contains 4.0.0. That is currently the only supported POM version, and is always required. [source]
But it wouldn't necessarily need to always...
HTML in string resource?
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You can also surround your html in a CDATA block as well and getString() will return your actual HTML. Like such:
<string name="foo"><![CDATA[Foo Bar <a href="foo?id=%s">baz</a> is cool]]></string>
Now when you perform a getString(R.string.foo) the...
Javascript Functions and default parameters, not working in IE and Chrome
...u can't do this, but you can instead do something like:
function saveItem(andClose) {
if(andClose === undefined) {
andClose = false;
}
}
This is often shortened to something like:
function setName(name) {
name = name || 'Bob';
}
Update
The above is true for ECMAScript <= 5. E...