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Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
How to trim a string in SQL Server before 2017?
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SELECT LTRIM(RTRIM(Names)) AS Names FROM Customer
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Copy/duplicate database without using mysqldump
...the references, you can run the following to copy the data:
INSERT INTO x SELECT * FROM other_db.y;
If you're using MyISAM, you're better off to copy the table files; it'll be much faster. You should be able to do the same if you're using INNODB with per table table spaces.
If you do end up doin...
How to open existing project in Eclipse
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Project > Import > General > Select Root Directory > (do NOT select copy projects into workspace). This is useful if you use Eclipse outside scope of Java project as well, such as Ruby projects or C projects.
– JohnMerlino
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Jar Mismatch Found 2 versions of android-support-v4.jar in the dependency list
...rong.
Step #2: Pick one of those two versions of the JAR, or pick the one from the "extras" area of your SDK installation.
Step #3: Put the right JAR in App Library.
Step #4: Delete the one from App Free, since it will pick up that JAR from App Library.
You are welcome to instead have the same a...
How do I check in SQLite whether a table exists?
...sed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FROM sqlite_master WHERE type='table' AND name='{table_name}';
Where {table_name} is the name of the table to check.
Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database S...
Build unsigned APK file with Android Studio
...nu in the toolbar at the top (Open 'Edit Run/Debug configurations' dialog)
Select "Edit Configurations"
Click the "+"
Select "Gradle"
Choose your module as a Gradle project
In Tasks: enter assemble
Press Run
Your unsigned APK is now located in
ProjectName\app\build\outputs\apk
For detailed inf...
How do I disable text selection with CSS or JavaScript? [duplicate]
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<div
style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;"
unselectable="on"
onselectstart="return false;"
onmousedown="return false;">
Blabla
</div>
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What is state-of-the-art for text rendering in OpenGL as of version 4.1? [closed]
...oaches to evaluate bezier curves in the pixel shader instead, these suffer from not being easily antialiased, which is trivial using a distance-map-textured quad, and evaluating curves in the shader is still computationally much more expensive than necessary.
The best trade-off between "fast" and "...
How to check if an option is selected?
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UPDATE
A more direct jQuery method to the option selected would be:
var selected_option = $('#mySelectBox option:selected');
Answering the question .is(':selected') is what you are looking for:
$('#mySelectBox option').each(function() {
if($(this).is(':selected')) ....