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What is the difference between JOIN and UNION?
... subsets it -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT...
Avoid passing null as the view root (need to resolve layout parameters on the inflated layout's root
Passing null for root studio gives me this warning:
7 Answers
7
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Is there a way for non-root processes to bind to “privileged” ports on Linux?
...recent kernel, it is indeed possible to use this to start a service as non-root but bind low ports. The short answer is that you do:
setcap 'cap_net_bind_service=+ep' /path/to/program
And then anytime program is executed thereafter it will have the CAP_NET_BIND_SERVICE capability. setcap is in th...
ORA-00979 not a group by expression
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@AaronDigulla That's what MySQL does, and the world didn't end :p
– Chris Baker
Aug 27 '14 at 21:32
1
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On delete cascade with doctrine2
...rine's cascade={"remove"} removes the related entities before removing the root entity (it has to). So when the root entity is deleted there aren't any foreign relations left for onDelete="CASCADE" to delete. But to be sure I would suggest you simply create a small test case and look at the queries ...
ActiveRecord.find(array_of_ids), preserving order
...
The answer is for mysql only
There is a function in mysql called FIELD()
Here is how you could use it in .find():
>> ids = [100, 1, 6]
=> [100, 1, 6]
>> WordDocument.find(ids).collect(&:id)
=> [1, 6, 100]
>> WordD...
Error: “The sandbox is not in sync with the Podfile.lock…” after installing RestKit with cocoapods
...
After many attemps I managed to fix this problem. Variable ${PODS_ROOT} was not set and I do below trick.
Go to Build Phases -> Check Pods Manifest.lock and replace
diff "${PODS_ROOT}/../Podfile.lock" "${PODS_ROOT}/Manifest.lock" > /dev/null
to
diff "${SRCROOT}/Podfile.lock" "${S...
PyCharm shows unresolved references error for valid code
...is information straight from the horses mouth: JetBrains - PyCharm Content Root "PyCharm uses the source roots as the starting point for resolving imports" I had the issue exactly as in the title because in some projects I need to use a file tree where sources are in a subfolder, PyCharm is then con...
JavaFX Application Icon
...on {
@Override
public void start(Stage stage) {
StackPane root = new StackPane();
// set icon
stage.getIcons().add(new Image("/path/to/stackoverflow.jpg"));
stage.setTitle("Wow!! Stackoverflow Icon");
stage.setScene(new Scene(root, 300, 250));
...
.htaccess rewrite to redirect root URL to subdirectory
...
You can use a rewrite rule that uses ^$ to represent the root and rewrite that to your /store directory, like this:
RewriteEngine On
RewriteRule ^$ /store [L]
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