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Why unsigned integer is not available in PostgreSQL?
...< 65536);
Here is what psql gives when I try to abuse the type.
DS1=# select (346346 :: uint2);
ERROR: value for domain uint2 violates check constraint "uint2_check"
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How to use GROUP_CONCAT in a CONCAT in MySQL
...
select id, group_concat(`Name` separator ',') as `ColumnName`
from
(
select
id,
concat(`Name`, ':', group_concat(`Value` separator ',')) as `Name`
from mytbl
group by
id,
`Name`
) tbl
group by id;
...
PostgreSQL Crosstab Query
... - not fit for missing attributes
crosstab(text) with 1 input parameter:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inacti...
Is it possible to declare two variables of different types in a for loop?
...ound (not that i'd actually use it unless forced to):
for(struct { int a; char b; } s = { 0, 'a' } ; s.a < 5 ; ++s.a)
{
std::cout << s.a << " " << s.b << std::endl;
}
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#define macro for debug printing in C?
...
#include <stdarg.h>
#include <stdio.h>
void dbg_printf(const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
vfprintf(stderr, fmt, args);
va_end(args);
}
You can also use this technique in C99, of course, but the __VA_ARGS__ technique is neater because it uses re...
Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
...erent type than the one seen by the compiler, for example:
struct S {
char a;
int b;
char c;
};
struct S_head {
char a;
};
struct S_ext {
char a;
int b;
char c;
int d;
char e;
};
struct S s;
struct S_head *head = (struct S_head*)&s;
fn1(head);
struct S_ex...
How can I compare two lists in python and return matches
... answer is more flexible and readable, since people may need difference or union.
– Shihe Zhang
Nov 1 '17 at 2:31
What...
Remove characters from C# string
... where char.IsWhiteSpace(c) || char.IsLetterOrDigit(c)
select c
).ToArray());
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Best approach for designing F# libraries for use from both F# and C#
...tten in a functional style (using F# function types, tuples, discriminated unions etc.)
.NET library is designed to be used from any .NET language (including C# and F#) and it typically follows .NET object-oriented style. This means that you'll expose most of the functionality as classes with method...
Insert Update trigger how to determine if insert or update
... track "before" and "after" data. So you can use something like IF EXISTS (SELECT * FROM DELETED) to detect an update. You only have rows in DELETED on update, but there are always rows in INSERTED.
Look for "inserted" in CREATE TRIGGER.
Edit, 23 Nov 2011
After comment, this answer is only for INSER...