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How to filter SQL results in a has-many-through relation
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Results:
Total runtimes from EXPLAIN ANALYZE.
1) Martin 2: 44.594 ms
SELECT s.stud_id, s.name
FROM student s
JOIN student_club sc USING (stud_id)
WHERE sc.club_id IN (30, 50)
GROUP BY 1,2
HAVING COUNT(*) > 1;
2) Erwin 1: 33.217 ms
SELECT s.stud_id, s.name
FROM student s
JOIN ...
Why is NaN not equal to NaN? [duplicate]
...c then you could get wildly incorrect (or worse: subtly incorrect) results from your calculations with no obvious indicator as to why.
There are also really good reasons for NaNs in calculations when probing the value of a mathematical function; one of the examples given in the linked document is ...
What arguments are passed into AsyncTask?
...here all the stuff you want to do in the background, in a different thread from the main one. Here we have as an input value an array of objects from the type “X” (Do you see in the header? We have “...extends AsyncTask” These are the TYPES of the input parameters) and returns an object from...
Behaviour for significant change location API when terminated/suspended?
This is the section from the CLLocationManager documentation describing the app behavior with startMonitoringSignificantLocationChanges :
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Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
...stem stored procs */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)
SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'P' AND category = 0 ORDER BY [name])
WHILE @name is not null
BEGIN
SELECT @SQL = 'DROP PROCEDURE [dbo].[' + RTRIM(@name) +']'
EXEC (@SQL)
PRINT ...
What is the smallest possible valid PDF?
... This will not work, you need to define a font resource and select it inside the page content for the text to show up.
– yms
Aug 21 '15 at 20:36
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Select random row from a sqlite table
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Have a look at Selecting a Random Row from an SQLite Table
SELECT * FROM table ORDER BY RANDOM() LIMIT 1;
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Is there a way to automate the android sdk installation?
... or its parts, even if something has been modified
-u --no-ui Updates from command-line (does not display the GUI)
-o --obsolete Installs obsolete packages
-t --filter A filter that limits the update to the specified types of packages in the form of
a comma-separated list ...
How do I find the location of the executable in C? [duplicate]
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To summarize:
On Unixes with /proc really straight and realiable way is to:
readlink("/proc/self/exe", buf, bufsize) (Linux)
readlink("/proc/curproc/file", buf, bufsize) (FreeBSD)
readlink("/proc/self/path/a.out", buf, bufsize) (Solaris)
On Unixes without /proc (i.e. if ab...
Why does this method print 4?
...P, then 0 will be printed. If P requires more space, then we remove frames from the stack, gaining R memory at the cost of cnt++.
When println is finally able to run, X - M - (C - cnt) * R >= P. So if P is large for a particular system, then cnt will be large.
Let's look at this with some exa...