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How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...
How to load assemblies in PowerShell?
...me;
These should also work:
Add-Type -AssemblyName $TypeName -PassThru | Select-Object -ExpandProperty Assembly | Select-Object -ExpandProperty FullName -Unique
If I want my script to always use a specific version of a .dll but I can't be certain of where it's installed, how do I determine what ...
How do you run a single query through mysql from the command line?
...
mysql -u <user> -p -e "select * from schema.table"
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How to export data as CSV format from SQL Server using sqlcmd?
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You can run something like this:
sqlcmd -S MyServer -d myDB -E -Q "select col1, col2, col3 from SomeTable"
-o "MyData.csv" -h-1 -s"," -w 700
-h-1 removes column name headers from the result
-s"," sets the column seperator to ,
-w 700 sets the row width to 700 chars (this will nee...
Access restriction: The type 'Application' is not API (restriction on required library rt.jar)
...s restrictions.
Go to the properties of your Java project,
i.e. by selecting "Properties" from the context menu of the project in the "Package Explorer".
Go to "Java Build Path", tab "Libraries".
Expand the library entry
select
"Access rules",
"Edit..." and
"Add..." a "Resolution: Ac...
How to set auto increment primary key in PostgreSQL?
...able(moobars,foobars) values('worldwide interblag','2012-05-02')
Step 3, select * from your table:
el@voyager$ psql -U pgadmin -d kurz_prod -c "select * from epictable"
Step 4, interpret the output:
mytable_key | moobars | foobars
-------------+-----------------------+------...
Android emulator doesn't take keyboard input - SDK tools rev 20
...elated note, if your tablet emulator is missing the BACK/HOME buttons, try selecting WXGA800 as the Built-in skin in the AVD editor:
Or by manually setting the skin in config.ini:
skin.name=WXGA800
skin.path=platforms/android-16/skins/WXGA800
(example is for API 16)
...
How to convert all text to lowercase in Vim
...ggVGu
Explanation:
gg - goes to first line of text
V - turns on Visual selection, in line mode
G - goes to end of file (at the moment you have whole text selected)
u - lowercase selected area
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:after vs. ::after
...nal difference between the CSS 2.1 :after and the CSS 3 ::after pseudo-selectors (other than ::after not being supported in older browsers)? Is there any practical reason to use the newer specification?
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Where is svn.exe in my machine?
... program is installed.
In the installer, the command line tools need to be selected for this:
(If you have already installed TortoiseSVN, then rerun the installer and select "Modify")
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