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Postgresql aggregate array
...
Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need ...
Why declare a struct that only contains an array in C?
...to char *, drastically reducing type-safety.
In summary:
typedef struct A_s_s { char m[113]; } A_s_t; // Full type safey, assignable
typedef char A_c_t[113]; // Partial type-safety, not assignable
A_s_t v_s(void); // Allowed
A_c_t v_c(void); // Forbid...
How do you detect/avoid Memory leaks in your (Unmanaged) code? [closed]
...e quick summary of those articles. First, include these headers:
#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>
Then you need to call this when your program exits:
_CrtDumpMemoryLeaks();
Alternatively, if your program does not exit in the same place every time, ...
Why doesn't Internet Explorer 11 honour conditional comments even when emulating Internet Explorer 8
...nd below (via conditional comments), and the browser simply ignores them. -_-
This feature worked perfectly fine in Internet Explorer 10, and Microsoft just had to tinker with it, didn't they?
<!--[if lte IE 8]><script src="ie8-html5.js"></script><![endif]-->
Apart from...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...
The default collation for stored procedure parameters is utf8_general_ci and you can't mix collations, so you have four options:
Option 1: add COLLATE to your input variable:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @r...
How to make Eclipse behave well in the Windows 7 taskbar?
...ecify the latest available Java VM in your eclipse.ini. I.e.:
-vm
jdk1.6.0_10\jre\bin\client\jvm.dll
Make sure they are on separate lines
Anything after the "vmargs" is taken to be vm arguments
(More info)
Or alternatively add the java bin folder to your Windows PATH before the "windows32" fo...
How do I tidy up an HTML file's indentation in VI?
...really want to, you can get those tags to be indented like so:
:let g:html_indent_inctags = "html,body,head,tbody"
See "HTML indenting not working in compiled Vim 7.4, any ideas?" and "alternative html indent script" for more information.
...
Should one call .close() on HttpServletResponse.getOutputStream()/.getWriter()?
...f it not closed.
public void close() throws IOException
{
if (_closed)
return;
if (!isIncluding() && !_generator.isCommitted())
commitResponse(HttpGenerator.LAST);
else
flushResponse();
super.close();
}
Also as ...
GoogleTest: How to skip a test?
...have a broken test that you cannot fix right away, you can add the DISABLED_ prefix to its name. This will exclude it from execution."
Examples:
// Tests that Foo does Abc.
TEST(FooTest, DISABLED_DoesAbc) { ... }
class DISABLED_BarTest : public ::testing::Test { ... };
// Tests that Bar does Xyz...
What does character set and collation mean exactly?
...
I suggest to use utf8mb4_unicode_ci, which is based on the Unicode standard for sorting and comparison, which sorts accurately in a very wide range of languages.
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