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How to get number of rows using SqlDataReader in C#
...reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete OHanlon) the second option is only concurrency-safe when you use a ...
How to get a list of column names on Sqlite3 database?
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but you can't select from that table. It's just plain annoying. I'm trying something like this... but it don't work create temporary table TmpCols (cid integer, name text, type text, nn bit, dflt_value, pk bit); .mode insert TmpCols .out...
form serialize javascript (no framework)
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Here is pure JavaScript approach:
var form = document.querySelector('form');
var data = new FormData(form);
var req = new XMLHttpRequest();
req.send(data);
Though it seems to be working only for POST requests.
https://developer.mozilla.org/en-US/docs/Web/API/FormData
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SQLite DateTime comparison
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I had the same issue recently, and I solved it like this:
SELECT * FROM table WHERE
strftime('%s', date) BETWEEN strftime('%s', start_date) AND strftime('%s', end_date)
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html select option separator
How do you make a separator in a select tag?
14 Answers
14
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Pandas - Get first row value of a given column
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To select the ith row, use iloc:
In [31]: df_test.iloc[0]
Out[31]:
ATime 1.2
X 2.0
Y 15.0
Z 2.0
Btime 1.2
C 12.0
D 25.0
E 12.0
Name: 0, dtype: float64
To select the ith val...
How to include “zero” / “0” results in COUNT aggregate?
...n outer join for this (and you need to use person as the "driving" table)
SELECT person.person_id, COUNT(appointment.person_id) AS "number_of_appointments"
FROM person
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is working, i...
What's the best UI for entering date of birth? [closed]
What is the best method for date of birth selector?
24 Answers
24
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How to get the first and last date of the current year?
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SELECT
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()), 0) AS StartOfYear,
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()) + 1, -1) AS EndOfYear
The above query gives a datetime value for midnight at the beginning of December 31. This ...
“No backupset selected to be restored” SQL Server 2012
...n I try with the UI approach ("Restore"), I get message @ top No backupset selected to be restored.
– The Red Pea
Apr 27 '17 at 16:50
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