大约有 43,000 项符合查询结果（耗时：0.0422秒） [XML]
Relative paths based on file location instead of current working directory [duplicate]
... have readlink, but has POSIX-compatible utilities - e.g., HP-UX (thanks, @Charles Duffy).
The following solution, inspired by https://stackoverflow.com/a/1116890/45375,
defines helper shell function, rreadlink(), which resolves a given symlink to its ultimate target in a loop - this function is i...
Postgres and Indexes on Foreign Keys and Primary Keys
...hema(s) from your program, all the information is on hand in the catalog:
select
n.nspname as "Schema"
,t.relname as "Table"
,c.relname as "Index"
from
pg_catalog.pg_class c
join pg_catalog.pg_namespace n on n.oid = c.relnamespace
join pg_catalog.pg_index ...
How to find all combinations of coins when given some dollar value
...n.
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
if (argc != 2)
{
printf("usage: change amount-in-cents\n");
return 1;
}
int total = atoi(argv[1]);
printf("quarter\tdime\tnickle\tpenny\tto make %d\n", total);
int co...
PostgreSQL - max number of parameters in “IN” clause?
...
explain select * from test where id in (values (1), (2));
QUERY PLAN
Seq Scan on test (cost=0.00..1.38 rows=2 width=208)
Filter: (id = ANY ('{1,2}'::bigint[]))
But if try 2nd query:
explain select * from test where id = an...
Dynamic SELECT TOP @var In SQL Server
...
SELECT TOP (@count) * FROM SomeTable
This will only work with SQL 2005+
share
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How to find the Number of CPU Cores via .NET/C#?
...ors:
foreach (var item in new System.Management.ManagementObjectSearcher("Select * from Win32_ComputerSystem").Get())
{
Console.WriteLine("Number Of Physical Processors: {0} ", item["NumberOfProcessors"]);
}
Cores:
int coreCount = 0;
foreach (var item in new System.Management.ManagementObjec...
Reshaping data.frame from wide to long format
...
Here is another example showing the use of gather from tidyr. You can select the columns to gather either by removing them individually (as I do here), or by including the years you want explicitly.
Note that, to handle the commas (and X's added if check.names = FALSE is not set), I am also us...
Android - Pulling SQlite database android device
...
Yes, this is because the / is as special string char. // in your "//" will result in /.
– KarlKarlsom
Apr 4 '12 at 14:36
4
...
Does a break statement break from a switch/select?
I know that switch / select statements break automatically after every case. I am wondering, in the following code:
6 Ans...
How can I use an array of function pointers?
...ived class.
Often you see something like this
struct function_table {
char *name;
void (*some_fun)(int arg1, double arg2);
};
void function1(int arg1, double arg2)....
struct function_table my_table [] = {
{"function1", function1},
...
So you can reach into the table by name and ca...