大约有 45,000 项符合查询结果（耗时：0.0502秒） [XML]
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...
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.
...
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...
How do you copy the contents of an array to a std::vector in C++ without looping?
...ven when a function expects c-style arrays you can use vectors:
vector<char> v(50); // Ensure there's enough space
strcpy(&v[0], "prefer vectors to c arrays");
Hope that helps someone out there!
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...
Zooming MKMapView to fit annotation pins?
...
I've also found this useful for selecting annotations outside the current visible map area. By default, MapView doesn't select non-visible annotations. Call showAnnotations with an array of your non-visible annotation(s), prior to calling selectAnnotation, ...
Python/postgres/psycopg2: getting ID of row just inserted
... case you can use:
cursor.execute('INSERT INTO ........')
cursor.execute('SELECT LASTVAL()')
lastid = cursor.fetchone()['lastval']
Just in case it was useful for anyone!
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improve this answe...
How to link to specific line number on github
...s://github.com/git/git/blob/master/README#L18
If you want multiple lines selected, simply hold down the shift key and click a second line number, like line 20. Looks like this:
And now your browser's URL looks like this:
https://github.com/git/git/blob/master/README#L18-L20
Here's the import...
Select Pandas rows based on list index
...
For large datasets, it is memory efficient to read only selected rows via the skiprows parameter.
Example
pred = lambda x: x not in [1, 3]
pd.read_csv("data.csv", skiprows=pred, index_col=0, names=...)
This will now return a DataFrame from a file that skips all rows except 1 and ...
jQuery: How can i create a simple overlay?
...
}
JavaScript
(function () {
// Add photo overlay hover behavior to selected images
$("img[data-photo-overlay='true']").mouseenter(showPhotoOverlay);
// Create photo overlay elements
var _isPhotoOverlayDisplayed = false;
var _photoId;
var _photoOverlay = $("<div id='ph...
Kill a postgresql session/connection
...user to use this function. This works on all operating systems the same.
SELECT
pg_terminate_backend(pid)
FROM
pg_stat_activity
WHERE
-- don't kill my own connection!
pid <> pg_backend_pid()
-- don't kill the connections to other databases
AND datname = 'database...