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Best way to test if a row exists in a MySQL table
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You could also try EXISTS:
SELECT EXISTS(SELECT * FROM table1 WHERE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything ...
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...
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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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 ...
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...
How can I select from list of values in SQL Server
... would be to use a find an replace with UNION to get the distinct values.
SELECT 1
UNION SELECT 1
UNION SELECT 1
UNION SELECT 2
UNION SELECT 5
UNION SELECT 1
UNION SELECT 6
Applied to your long line of comma delimited text
Find and replace every comma with UNION SELECT
Add a SELECT in front of ...
Why is unsigned integer overflow defined behavior but signed integer overflow isn't?
...he same representation used by the CPU - so the overflow behavior followed from the integer representation used by the CPU.
In practice, it is only the representations for signed values that may differ according to the implementation: one's complement, two's complement, sign-magnitude. For an unsign...
What is the proper declaration of main?
...? What is the correct return type, and what does it mean to return a value from main ? What are the allowed parameter types, and what are their meanings?
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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 ...
How can HTML5 “replace” Flash? [closed]
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What Adobe ought to do is incorporate canvas support from the flash IDE = ie, do all your animation in the IDE and output an HTML5 ready package of markup, css, and js. Give people the choice of output, the way they do with AIR. It would absolutely ensure the longevity of the F...