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What is the difference between UNION and UNION ALL?
...want the duplicates (especially when developing reports).
UNION Example:
SELECT 'foo' AS bar UNION SELECT 'foo' AS bar
Result:
+-----+
| bar |
+-----+
| foo |
+-----+
1 row in set (0.00 sec)
UNION ALL example:
SELECT 'foo' AS bar UNION ALL SELECT 'foo' AS bar
Result:
+-----+
| bar |
+---...
What does PermGen actually stand for?
...n specific.
Briefly, it contains the Java objects associated with classes and interned strings. In Sun's client implementation with sharing on, classes.jsa is memory mapped to form the initial data, with about half read-only and half copy-on-write.
Java objects that are merely old are kept in the ...
AngularJS - Trigger when radio button is selected
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I just want to call some function in the controller when radio button is selected.
7 Answers
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How to select a node using XPath if sibling node has a specific value?
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Q: How to select a node using XPath if sibling node has a specific value?
Because there are only "XPath Axes" for following-siblings and preceding-siblings, you can use one of them if the position is fixed.
But better:
Look for cc w...
What is the PostgreSQL equivalent for ISNULL()
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SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
share...
Why can't radio buttons be “readonly”?
...ton by disabling only the un-checked radio buttons. It keeps the user from selecting a different value, and the checked value will always post on submit.
Using jQuery to make readonly:
$(':radio:not(:checked)').attr('disabled', true);
This approach also worked for making a select list readonly, ...
How to set up Android emulator proxy settings
I want to to use the browser inside the Android emulator, and I want to use the proxy settings on my machine. How can I set this up?
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SQLAlchemy: print the actual query
...s:
print(str(statement))
This applies both to an ORM Query as well as any select() or other statement.
Note: the following detailed answer is being maintained on the sqlalchemy documentation.
To get the statement as compiled to a specific dialect or engine, if the statement itself is not already bo...
Xcode stops working after set “xcode-select -switch”
...eloper directory, not the Xcode application bundle. Run this:
sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer
With recent versions of Xcode, you can go to Xcode ➙ Preferences… ➙ Locations and pick one of the options for Command Line Tools to set the location.
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Getting the names of all files in a directory with PHP
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Don't bother with open/readdir and use glob instead:
foreach(glob($log_directory.'/*.*') as $file) {
...
}
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