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Is there a difference between “==” and “is”?
...ound that: echo 'import sys;tt=sys.argv[1];print(tt is "foo", tt == "foo", id(tt)==id("foo"))'| python3 - foo output: False True False.
– ahuigo
Jul 23 '18 at 12:38
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What are detached, persistent and transient objects in hibernate?
...ot associated with a Session, has no representation in the database and no identifier value is considered transient by Hibernate:
Person person = new Person();
person.setName("Foobar");
// person is in a transient state
A persistent instance has a representation in the database, an identifier va...
How to check if a process id (PID) exists
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To check for the existence of a process, use
kill -0 $pid
But just as @unwind said, if you're going to kill it anyway, just
kill $pid
or you will have a race condition.
If you want to ignore the text output of kill and do something based on the exit code, you can
if ! kill...
Should I use px or rem value units in my CSS? [closed]
...u have to press Alt, and go to View, Text Size.) It's much easier to just select the Zoom option in the browser's main menu (or use Ctrl++/-/mouse wheel).
1 - within statistical error, naturally
If we assume most users scale pages using the zoom option, I find relative units mostly irrelevant. I...
Checking for a null int value from a Java ResultSet
...yAppearingStmt.executeQuery(query);
if (rs.next()) {
iVal = rs.getInt("ID_PARENT");
if (rs.wasNull()) {
// handle NULL field value
}
}
(Edited as @martin comments below; the OP code as written would not compile because iVal is not initialised)
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How to change color of Android ListView separator line?
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You can set this value in a layout xml file using android:divider="#FF0000". If you are changing the colour/drawable, you have to set/reset the height of the divider too.
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_c...
Google Maps: How to create a custom InfoWindow?
...e your links and demo map as they don't work.
– MrUpsidown
Nov 12 '19 at 9:51
add a comment
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Objective-C pass block as parameter
...g the * with a ^. One way to pass a block to a method is as follows:
- (void)iterateWidgets:(void (^)(id, int))iteratorBlock;
But as you can see, that's messy. You can instead use a typedef to make block types cleaner:
typedef void (^ IteratorBlock)(id, int);
And then pass that block to a meth...
How do I tell if a regular file does not exist in Bash?
...tmp/foo.txt ] && echo "File not found!"
– DavidWinterbottom
Sep 29 '10 at 12:09
38
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Update one MySQL table with values from another
...NNER JOIN original ON (tobeupdated.value = original.value)
SET tobeupdated.id = original.id
That should do it, and really its doing exactly what yours is. However, I prefer 'JOIN' syntax for joins rather than multiple 'WHERE' conditions, I think its easier to read
As for running slow, how large a...