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What is the dual table in Oracle?
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It's a sort of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
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Max or Default?
...d, you can get around this limitation by casting to a nullable within your select. My VB is a little rusty, but I think it'd go something like this:
Dim x = (From y In context.MyTable _
Where y.MyField = value _
Select CType(y.MyCounter, Integer?)).Max
Or in C#:
var x = (from y...
How to display default text “--Select Team --” in combo box on pageload in WPF?
...ComboBox Name="MyComboBox"
IsEditable="True"
IsReadOnly="True"
Text="-- Select Team --" />
You'll obviously need to add your other options, but this is probably the simplest way to do it.
There is however one downside to this method which is while the text inside your combo box will not be ...
How to change Android Studio's editor font?
...TRL + mouse wheel which is really easy to use it !!!
To use this feature select File -> Settings -> Editor -> General -> select the checkbox of Change the font size (Zoom) with Ctrl + Mouse Wheel
I hope it's helpful.
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Update statement with inner join on Oracle
...sn't valid in Oracle. You can do this:
UPDATE table1 SET table1.value = (SELECT table2.CODE
FROM table2
WHERE table1.value = table2.DESC)
WHERE table1.UPDATETYPE='blah'
AND EXISTS (SELECT table2.CODE
FROM table2
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Oracle “Partition By” Keyword
...d then use that in a calculation against this records salary without a sub select, which is much faster.
Read the linked AskTom article for further details.
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✔ Checkmark selected row in UITableViewCell
...pment newbie. I want to add a checkmark to my UITableViewCell when it is selected. The checkmark should be removed when another row is selected. How would I do this?
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Why is there no tuple comprehension in Python?
...because tuple syntax and parenthesis are ambiguous
– Charles Salvia
Jun 5 '13 at 13:14
21
The dif...
XPath: How to select nodes which have no attributes?
Using XPath, how to select nodes which have no attributes (where attribute count = 0)?
3 Answers
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What does the “__block” keyword mean?
...c NSInteger CounterStatic;
{
NSInteger localCounter = 42;
__block char localCharacter;
void (^aBlock)(void) = ^(void) {
++CounterGlobal;
++CounterStatic;
CounterGlobal = localCounter; // localCounter fixed at block creation
localCharacter = 'a'; // sets ...