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'IF' in 'SELECT' statement - choose output value based on column values
...IF(type = 'P', amount, amount * -1) as amount
FROM report
See http://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as...
Favourite performance tuning tricks [closed]
...
Assuming MySQL here, use EXPLAIN to find out what is going on with the query, make sure that the indexes are being used as efficiently as possible and try to eliminate file sorts. High Performance MySQL: Optimization, Backups, Replica...
Find and Replace Inside a Text File from a Bash Command
... I stumbled over this...
There is a replace command which ships with the "mysql-server" package, so if you have installed it try it out:
# replace string abc to XYZ in files
replace "abc" "XYZ" -- file.txt file2.txt file3.txt
# or pipe an echo to replace
echo "abcdef" |replace "abc" "XYZ"
See m...
How to extract a git subdirectory and make a submodule out of it?
...nstall
Usage
Split a larger into smaller chunks:
# Go into the project root
cd ~/my-project
# Create a branch which only contains commits for the children of 'foo'
git subtree split --prefix=foo --branch=foo-only
# Remove 'foo' from the project
git rm -rf ./foo
# Create a git repo for 'foo' (...
How do I load an org.w3c.dom.Document from XML in a string?
...me up with. It's mostly the same solution as before, augmented to get the root element down as a NodeList and using erickson's suggestion of using an InputSource instead for character encoding issues.
private String DOC_ROOT="root";
String xml=getXmlString();
Document xmlDoc=loadXMLFrom(xml);
Elem...
Find all files in a directory with extension .txt in Python
...file))
or if you want to traverse directory, use os.walk:
import os
for root, dirs, files in os.walk("/mydir"):
for file in files:
if file.endswith(".txt"):
print(os.path.join(root, file))
share
...
Update Git submodule to latest commit on origin
... branch
git checkout master
# Update
git pull
# Get back to your project root
cd ..
# Now the submodules are in the state you want, so
git commit -am "Pulled down update to submodule_dir"
Or, if you're a busy person:
git submodule foreach git pull origin master
...
Elegant setup of Python logging in Django
...quirements. The key thing is that I usually add the handlers I want to the root logger, using levels and sometimes logging.Filters to get the events I want to the appropriate files, console, syslogs etc. You can of course add handlers to any other loggers too, but there isn't commonly a need for thi...
How to find unused images in an Xcode project?
...re, and you just execute it from whatever directory you want to use as the root for searching for images (e.g. your project root folder). You can put it in ~/script/ for example and then go to your project root folder and run it by pointing to the script directly: ~/script/unused_images.sh
...
Dependent DLL is not getting copied to the build output folder in Visual Studio
...Build errors were that Project A, B, C, Y, and X dlls could not be found.
Root cause was that newly created Project X targeted .NET 4.5 while the rest of the solution projects targeted .NET 4.5.1. Project X didn't build causing the rest of the Projects to not build either.
Make sure any newly add...