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How to select multiple rows filled with constants?
Selecting constants without referring to a table is perfectly legal in an SQL statement:
15 Answers
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Caveats of select/poll vs. epoll reactors in Twisted
...o based apps ) leads me to believe that ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
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Get selected value in dropdown list using JavaScript
How do I get the selected value from a dropdown list using JavaScript?
28 Answers
28
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Rails select helper - Default selected value, how?
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This should do it:
<%= f.select :project_id, @project_select, :selected => params[:pid] %>
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How to randomly select rows in SQL?
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SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT...
Blank HTML SELECT without blank item in dropdown list
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Just use disabled and/or hidden attributes:
<option selected disabled hidden style='display: none' value=''></option>
selected makes this option the default one.
disabled makes this option unclickable.
style='display: none' makes this option not displayed in older ...
Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...
Selecting all text in HTML text input when clicked
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You can use this javascript snippet:
<input onClick="this.select();" value="Sample Text" />
But apparently it doesn't work on mobile Safari. In those cases you can use:
<input onClick="this.setSelectionRange(0, this.value.length)" value="Sample Text" />
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How to strip all non-alphabetic characters from string in SQL Server?
...ex(@KeepValues, @Temp), 1, '')
Return @Temp
End
Call it like this:
Select dbo.RemoveNonAlphaCharacters('abc1234def5678ghi90jkl')
Once you understand the code, you should see that it is relatively simple to change it to remove other characters, too. You could even make this dynamic enough ...
Generating random strings with T-SQL
...st varchar(8000)
declare @step bigint = rand(@seed) * 2147483647;
select @alpha = 'qwertyuiopasdfghjklzxcvbnm'
, @digit = '1234567890'
, @specials = '_@# '
select @first = @alpha + '_@';
set @seed = (rand((@seed+@step)%2147483647)*2147483647);
select @length =...