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How can I use swift in Terminal?
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sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
then you can do one of these:
xcrun swift
lldb --repl
As of Xcode 6.1 - typing swift in the terminal launches the REPL as well.
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COUNT DISTINCT with CONDITIONS
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You can try this:
select
count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex...
T-SQL CASE Clause: How to specify WHEN NULL
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Given your query you can also do this:
SELECT first_name + ' ' + ISNULL(last_name, '') AS Name FROM dbo.person
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Difference between clustered and nonclustered index [duplicate]
...a completely different object within the table that contains the column(s) selected for indexing and a pointer back to the table’s rows containing the data. It is like an index in the last pages of a book, where keywords are sorted and contain the page number to the material of the book for faster...
How to create a memory leak in Java?
...odecs). This can happen when the lib is loaded outside your application's root classloader but holds references to your classes (eg. by caching). When you undeploy/redeploy your app the JVM is unable to garbage collect the app's classloader (and therefore all classes loaded by it), so with repeat ...
AngularJS- Login and Authentication in each route and controller
...our main controller you watch if the state of the user change.
app.run(['$rootScope', '$location', 'Auth', function ($rootScope, $location, Auth) {
$rootScope.$on('$routeChangeStart', function (event) {
if (!Auth.isLoggedIn()) {
console.log('DENY');
event.preven...
Graph Algorithm To Find All Connections Between Two Arbitrary Vertices
...ersal. With breadth first you first visit all nodes with distance 0 to the root, then those with distance 1, then 2, etc.
– mweerden
Sep 12 '08 at 20:48
14
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How to create circle with Bézier curves?
...nnot be expressed exactly with a cubic, because a circle contains a square root in its equation. As a consequence, you have to approximate.
To do this, you have to divide your circle in n-tants (e.g.quadrants, octants). For each n-tant, you use the first and last point as the first and last of the ...
Standard alternative to GCC's ##__VA_ARGS__ trick?
...ine REST_HELPER_TWOORMORE(first, ...) , __VA_ARGS__
#define NUM(...) \
SELECT_10TH(__VA_ARGS__, TWOORMORE, TWOORMORE, TWOORMORE, TWOORMORE,\
TWOORMORE, TWOORMORE, TWOORMORE, TWOORMORE, ONE, throwaway)
#define SELECT_10TH(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, ...) a10
int
main...
How much faster is C++ than C#?
...ted and error prone.
As Donald Knuth said, "premature optimization is the root of all evil". If you really know for sure that your application will mostly consist of very performance critical arithmetic, and that it will be the bottleneck, and it's certainly going to be faster in C++, and you're su...