大约有 44,000 项符合查询结果（耗时：0.0349秒） [XML]
How to check whether a file is empty or not?
... my_file.seek(0) #ensure you're at the start of the file..
... first_char = my_file.read(1) #get the first character
... if not first_char:
... print "file is empty" #first character is the empty string..
... else:
... my_file.seek(0) #first character wasn't empty, retu...
ORDER BY the IN value list
... (introduced in PostgreSQL 8.2) VALUES (), ().
Syntax will be like this:
select c.*
from comments c
join (
values
(1,1),
(3,2),
(2,3),
(4,4)
) as x (id, ordering) on c.id = x.id
order by x.ordering
share...
Select2 doesn't work when embedded in a bootstrap modal
When I use a select2 (input) in bootstrap modal, I can't type anything into it. It's like disabled? Outside the modal select2 works fine.
...
How to convert SecureString to System.String?
...e(value);
for (int i=0; i < value.Length; i++) {
short unicodeChar = Marshal.ReadInt16(valuePtr, i*2);
// handle unicodeChar
}
} finally {
Marshal.ZeroFreeGlobalAllocUnicode(valuePtr);
}
}
sha...
React JSX: selecting “selected” on selected option
In a React component for a <select> menu, I need to set the selected attribute on the option that reflects the application state.
...
Optimal way to concatenate/aggregate strings
...Transact SQL, which should work fine in Azure.
;WITH Partitioned AS
(
SELECT
ID,
Name,
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY Name) AS NameNumber,
COUNT(*) OVER (PARTITION BY ID) AS NameCount
FROM dbo.SourceTable
),
Concatenated AS
(
SELECT
...
MySQL Query to select data from last week?
Hi I have a table with a date field and some other information.
I want to select all entries from the past week, (week start from Sunday).
...
Which, if any, C++ compilers do tail-recursion optimization?
...t for program correctness.
#include <stdio.h>
static int atoi(const char *str, int n)
{
if (str == 0 || *str == 0)
return n;
return atoi(str+1, n*10 + *str-'0');
}
int main(int argc, char **argv)
{
for (int i = 1; i != argc; ++i)
printf("%s -> %d\n", argv[i], at...
Selecting empty text input using jQuery
...ow do I identify empty textboxes using jQuery? I would like to do it using selectors if it is at all possible. Also, I must select on id since in the real code where I want to use this I don't want to select all text inputs.
...
LEFT JOIN only first row
...rtist_id) will be the earliest.
So try something like this (untested...)
SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
SELECT
MIN(fa.artist_id) a_id
FROM feeds_artists fa
WHERE fa.feed_id = f.feed_id
) a
...