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Factors in R: more than an annoyance?
...ls(x)
levels(x$Species)
# [1] "setosa"
This is how to keep levels you've selected out from getting in ggplot legends.
Internally, factors are integers with an attribute level character vector (see attributes(iris$Species) and class(attributes(iris$Species)$levels)), which is clean. If you had to ...
WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
...rence in certain circumstances.
So use WITH (NOLOCK) if the current data selected is allowed to be incorrect, as it might be rolled back later. This is mostly used when you want to increase performance, and the requirements on your application context allow it to take the risk that inconsistent da...
Can the C# interactive window interact with my code?
...n use classes from your own project.
Just right click on your solution and select "Reset Interactive from Project".
If you need more information, here is the source:
Using the C# Interactive Window that comes with Roslyn – Part 2
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What reason is there to use null instead of undefined in JavaScript?
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This should have been the selected answer
– alaboudi
Mar 1 at 6:19
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In .NET, which loop runs faster, 'for' or 'foreach'?
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Enumerable.Select has an overload that lets you obtain the index of the item, so even the need for an index does not mandate using for. See msdn.microsoft.com/en-us/library/bb534869.aspx
– TrueWill
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How do you run CMD.exe under the Local System Account?
...n interactive desktop and once you see it you have to press Win+U and then select OSK you will get CMD.exe running under Local system privileges. There are even more ways to get local system access with CMD
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How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?
...ysqldump fare with large databases in terms of performance? Any way to use SELECT INTO OUTFILE and LOAD DATA smoothly in your suggested process? (Since they generally perform faster)
– Ifedi Okonkwo
Jul 12 '16 at 19:35
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How do I create an Excel (.XLS and .XLSX) file in C# without installing Microsoft Office?
...te a query and fill the data table with the data from the DB
string sql = "SELECT Whatever FROM MyDBTable;";
OleDbCommand cmd = new OleDbCommand(sql, con);
OleDbDataAdapter adptr = new OleDbDataAdapter();
adptr.SelectCommand = cmd;
adptr.Fill(dt);
con.Close();
//Add the table to the data set
ds.Ta...
“tag already exists in the remote" error after recreating the git tag
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In Mac SourceTree only deselect the Push all tags checkbox:
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Difference between an application server and a servlet container?
... I don't think a generic flowchart approach is applicable here.
Platform selection is usually done by weighing specific requirements against first-hand knowledge of systems under consideration.
However the question gives no clues as to what the evaluation criteria are. Should it be open source? ...