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PostgreSQL: Drop PostgreSQL database through command line [closed]
...rrently taking place against your database, including all idle processes.
SELECT * FROM pg_stat_activity WHERE datname='database name';
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SQL Server Insert if not exists
..., Assunto, Data)
VALUES (@_DE, @_ASSUNTO, @_DATA)
WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos
WHERE De = @_DE
AND Assunto = @_ASSUNTO
AND Data = @_DATA);
END
replace with
BEGIN
IF NOT EXISTS (SELECT * FROM EmailsRecebidos
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How do you bind an Enum to a DropDownList control in ASP.NET?
...t; o.EnumProperty, Enum.GetValues(typeof(enumtype)).Cast<enumtype>().Select(x => new SelectListItem { Text = x.ToString(), Value = ((int)x).ToString() }))
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jQuery $(“#radioButton”).change(…) not firing during de-selection
...Andomar's solution worked but this makes more sense to me. Using the class selector prevents having to change the function if the form changes or has a dynamic number of fields. Yay for necro votes! (though now 2 years later jQuery recommends using prop() instead of attr(). api.jquery.com/prop)
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SQL how to make null values come last when sorting ascending
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select MyDate
from MyTable
order by case when MyDate is null then 1 else 0 end, MyDate
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Why can't radio buttons be “readonly”?
...ton by disabling only the un-checked radio buttons. It keeps the user from selecting a different value, and the checked value will always post on submit.
Using jQuery to make readonly:
$(':radio:not(:checked)').attr('disabled', true);
This approach also worked for making a select list readonly, ...
Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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How do I use prepared statements in SQlite in Android?
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@jasonhudgins Why not just replace your SELECT with an INSERT? I just came from this thread, where you've confused a beginner
– keyser
May 3 '14 at 15:29
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postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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