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Change R default library path using .libPaths in Rprofile.site fails to work
...ite settings or perhaps is overriding them by reading an .Rprofile setting from one of the RStudio defaults. It should also be mentioned that the result from this operation also appends the contents of calls to .Library and .Library.site, which is further reason why an RStudio- (or any other IDE or ...
What is the difference between a directory and a folder?
Most people use the terms "folder" and "directory" interchangeably. From a programmer point of view, is there a difference, and if so, what is it? Does it depend on the OS, or is there a broad, general consensus? This at least suggests that there is a difference.
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MySQL: Order by field size/length
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SELECT * FROM TEST ORDER BY LENGTH(description) DESC;
The LENGTH function gives the length of string in bytes. If you want to count (multi-byte) characters, use the CHAR_LENGTH function instead:
SELECT * FROM TEST ORDER BY...
View contents of database file in Android Studio
...File Explorer (one of the tabs on the right), go to /data/data/databases
Select the database by just clicking on it.
Go to the top right corner of the Android Device Monitor window. Click on the 'pull a file from the device' button:
A window will open asking you where you want to save your data...
What is a “batch”, and why is GO used?
...add a column to a table, then it should be in its own batch.
If you try to SELECT the new column in the same batch it fails because at parse/compile time the column does not exist.
GO is used by the SQL tools to work this out from one script: it is not a SQL keyword and is not recognised by the eng...
How to exclude particular class name in CSS selector?
...
One way is to use the multiple class selector (no space as that is the descendant selector):
.reMode_hover:not(.reMode_selected):hover
{
background-color: #f0ac00;
}
<a href="" title="Design" class="reMode_design reMode_hover">
<span&...
Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
... up the firstname field as shown.
http://localhost:8983/solr/collection1/select?q=firstname:john^2&lastname:john
As you can see, firstname field is boosted up with a score of 2.
More on SolrRelevancy
searching and indexing speed
The speed is unbelievably fast and no compromise o...
Folder is locked and I can't unlock it
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Right click on your Subversion working directory folder, and select TortoiseSVN->Clean Up from the Context Menu. This will recurse it's way through your working directory and cleanup any incomplete actions, remove the local locks (which is different from using Subversion locking of ...
Should I use the datetime or timestamp data type in MySQL?
...o with the native format. You can do calculations within MySQL that way
("SELECT DATE_ADD(my_datetime, INTERVAL 1 DAY)") and it is simple to change the format of the value to a UNIX timestamp ("SELECT UNIX_TIMESTAMP(my_datetime)") when you query the record if you want to operate on it with PHP.
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Visual Studio refuses to forget breakpoints?
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Try this select the Breakpoints toolbar item from the Debug toolbar. This brings up the Breakpoints window. From this window, you can view all breakpoints in the application. Here, you select and clear the breakpoint by clicking the D...