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c# datatable to csv
...s = dt.Columns.Cast<DataColumn>().
Select(column => column.ColumnName).
ToArray();
sb.AppendLine(string.Join(",", columnNames));
foreach (DataRow row in dt.Rows)
{
string[] fields = row.ItemArray.Select(field => fie...
Is it possible to GROUP BY multiple columns using MySQL?
Is it possible to GROUP BY more than one column in a MySQL SELECT query? For example:
7 Answers
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jquery selector for id starts with specific text [duplicate]
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Use jquery starts with attribute selector
$('[id^=editDialog]')
Alternative solution - 1 (highly recommended)
A cleaner solution is to add a common class to each of the divs & use
$('.commonClass').
But you can use the first one if html markup i...
Install MySQL on Ubuntu without a password prompt
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sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your_password'
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password_again password your_password'
sudo apt-get -y install ...
how to fire event on file select
...d the same file again? This code will only execute once, the second time, selecting the same file will not execute a change event
– Christopher Thomas
Mar 13 '14 at 15:11
6
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creating a random number using MYSQL
I would like to know is there a way to select randomly generated number between 100 and 500 along with a select query.
6 A...
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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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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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 check if field is null or empty in MySQL?
...
Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
...