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Surrogate vs. natural/business keys [closed]
...ot more tables into your query than should really be necessary. Compare:
select sum(t.hours)
from timesheets t
where t.dept_code = 'HR'
and t.status = 'VALID'
and t.project_code = 'MYPROJECT'
and t.task = 'BUILD';
against:
select sum(t.hours)
from timesheets t
join departents d on d.dept_i...
Pass a data.frame column name to a function
...(x[,column])
}
fun1(df, "B", max)
Alternatively, using [[ also works for selecting a single column at a time:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[[column]])
}
fun1(df, "B")
...
Custom fonts in iOS 7
... font you imported to your app is being packed into app itself. Do that by selecting your Target, then Build Phases, then Copy Bundle Resources. If you don't see your font in there, drag it from Supporting Files.
Finally, you would like to list all your fonts when the app starts just to see useabl...
How to get the list of all installed color schemes in Vim?
...a list of all installed color schemes in Vim? That would make very easy to select one without looking at the .vim directory.
...
Failed to load c++ bson extension
...vailable when you installed your mongodb library. I suggest you do
xcode-select --install (on a mac)
or sudo apt-get install gcc make build-essential (on ubuntu)
and run
rm -rf node_modules
npm cache clean
npm install
OR just npm update based on @tobias comment (after installing build-essenti...
Word wrap for a label in Windows Forms
...
Select the label you're dynamically adding text to. Look at the properties for the label and turn off AutoSize. You will now be able to drag/set the area for the label and it will automatically auto-wrap to stay within those...
How to increase font size in NeatBeans IDE?
...
In OS X, Netbeans 8.0
Use Command + , to open the options
Select Fonts & Colors tab
Click the button in the Font section (button is next to the Font textbox)
Change the Font, style and size as needed
...
Maintain/Save/Restore scroll position when returning to a ListView
... - mList.getPaddingTop());
// ...
// restore index and position
mList.setSelectionFromTop(index, top);
Explanation:
ListView.getFirstVisiblePosition() returns the top visible list item. But this item may be partially scrolled out of view, and if you want to restore the exact scroll position of t...
How to upgrade all Python packages with pip?
... install pip-review
$ py -3 -m pip_review --local --interactive
You can select 'a' to upgrade all packages; if one upgrade fails, run it again and it continues at the next one.
share
|
improve th...
Build project into a JAR automatically in Eclipse
...con on build.xml.
Step 2
Right-click on the root node in the project.
- Select Properties
- Select Builders
- Select New
- Select Ant Build
- In the Main tab, complete the path to the build.xml file in the bin folder.
Check the Output
The Eclipse output window (named Console) should show...