大约有 43,000 项符合查询结果（耗时：0.0426秒） [XML]
How would you do a “not in” query with LINQ?
...from c in dc.Customers
where !(from o in dc.Orders
select o.CustomerID)
.Contains(c.CustomerID)
select c;
foreach (var c in query) Console.WriteLine( c );
from The NOT IN clause in LINQ to SQL by Marco Russo
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How to find a hash key containing a matching value
...
You could use Enumerable#select:
clients.select{|key, hash| hash["client_id"] == "2180" }
#=> [["orange", {"client_id"=>"2180"}]]
Note that the result will be an array of all the matching values, where each is an array of the key and value.
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SQL Server: Get data for only the past year
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The following adds -1 years to the current date:
SELECT ... From ... WHERE date > DATEADD(year,-1,GETDATE())
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follo...
Define static method in source-file with declaration in header-file in C++
...case,
static void CP_StringToPString( std::string& inString, unsigned char *outString);
Since your member function CP_StringToPstring is static, the parameters in that function, inString and outString should be declared as static too.
The static member functions does not refer to the object ...
Python Pandas: Get index of rows which column matches certain value
... [57]: idx
Out[57]: Int64Index([10, 40, 50], dtype='int64')
then you can select the rows using loc instead of iloc:
In [58]: df.loc[idx]
Out[58]:
BoolCol
10 True
40 True
50 True
[3 rows x 1 columns]
Note that loc can also accept boolean arrays:
In [55]: df.loc[df['BoolCol']]
Ou...
SQL Server Management Studio, how to get execution time down to milliseconds
...able in your proc:
DECLARE @EndTime datetime
DECLARE @StartTime datetime
SELECT @StartTime=GETDATE()
-- Write Your Query
SELECT @EndTime=GETDATE()
--This will return execution time of your query
SELECT DATEDIFF(ms,@StartTime,@EndTime) AS [Duration in millisecs]
AND see this
Measuring Quer...
How to use LINQ to select object with minimum or maximum property value
...>(this IEnumerable<TSource> source,
Func<TSource, TKey> selector)
{
return source.MinBy(selector, null);
}
public static TSource MinBy<TSource, TKey>(this IEnumerable<TSource> source,
Func<TSource, TKey> selector, IComparer<TKey> comparer)
{
if...
Why was the switch statement designed to need a break?
...
To implement Duff's device, obviously:
dsend(to, from, count)
char *to, *from;
int count;
{
int n = (count + 7) / 8;
switch (count % 8) {
case 0: do { *to = *from++;
case 7: *to = *from++;
case 6: *to = *from++;
case 5: *to = *from++;
case 4: ...
Auto-expanding layout with Qt-Designer
...your widget/dialog/window (not the QVBoxLayout, but the parent widget) and select Lay Out -> Lay Out in a Grid from the bottom of the context-menu. The QVBoxLayout should now stretch to fit the window and will resize automatically when the entire window is resized.
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Is there a command to refresh environment variables from the command prompt in Windows?
... Path_HKCU >> "%TEMP%\_env.cmd"
:: Caution: do not insert space-chars before >> redirection sign
echo/set Path=%%Path_HKLM%%;%%Path_HKCU%% >> "%TEMP%\_env.cmd"
:: Cleanup
del /f /q "%TEMP%\_envset.tmp" 2>nul
del /f /q "%TEMP%\_envget.tmp" 2>nul
:: S...