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Update all objects in a collection using LINQ
...nsion method, if you want to use just the framework you can do
collection.Select(c => {c.PropertyToSet = value; return c;}).ToList();
The ToList is needed in order to evaluate the select immediately due to lazy evaluation.
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Getting the encoding of a Postgres database
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A programmatic solution:
SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = 'yourdb';
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Read data from SqlDataReader
...you use indexes like reader.GetString(0) will it use the first column you selected in your query or the firstt column on the table. I have a table with 3 columns in order: ID, Dir, Email. My command selects dir and email. Will reader.GetStrting(0) retrieve dir or ID? Are the indexes based off t...
Login failed for user 'DOMAIN\MACHINENAME$'
...curity >> Logins and right click on NT AUTHORITY\NETWORK SERVICE and select Properties
In newly opened screen of Login Properties, go to the “User Mapping” tab. Then, on the “User Mapping” tab, select the desired database – especially the database for which this error message is dis...
Speed up the loop operation in R
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Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
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How to remove a field from params[:something]
...elete you can do a memo:
def parameters
@parameters ||= params.require(:root).permit(:foo, :bar)
end
Now you can do:
parameteres.delete(:bar)
parameters
=> <ActionController::Parameters {"foo" => "foo"} permitted: true>
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How can I convert a string to upper- or lower-case with XSLT?
...hod of case conversion is translate():
<xsl:variable name="lowercase" select="'abcdefghijklmnopqrstuvwxyz'" />
<xsl:variable name="uppercase" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'" />
<xsl:template match="/">
<xsl:value-of select="translate(doc, $lowercase, $uppercase)" /&g...
Can anyone explain python's relative imports?
...rom relative.py
Hello from parent.py
Also it's better to use import from root folder, i.e.:
- sub/start.py
import sub.relative
import parent
Run it like:
PYTHONPATH='.' python3 sub/start.py
Output:
Hello from relative.py
Hello from parent.py
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Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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Get size of folder or file
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Be careful if you run this in the C: root directory on a Windows machine; there's a system file there which is (according to java.io.File) neither a file nor a directory. You might want to change the else-clause to check that the File is actually a directory.
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