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Immutable vs Mutable types
...'bar'
print s # foobar
The value of the variable changes, but it changes by changing what the variable refers to. A mutable type can change that way, and it can also change "in place".
Here is the difference.
x = something # immutable type
print x
func(x)
print x # prints the same thing
x = som...
How do you determine what SQL Tables have an identity column programmatically
...ject_id(TABLE_SCHEMA+'.'+TABLE_NAME), COLUMN_NAME, 'IsIdentity') = 1
order by TABLE_NAME
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Select2 dropdown but allow new values by user?
...
For version 4+ check this answer below by Kevin Brown
In Select2 3.5.2 and below, you can use something like:
$(selector).select2({
minimumInputLength:1,
"ajax": {
data:function (term, page) {
return { term:term, page:page };
},
dataType:"j...
How can I pass selected row to commandLink inside dataTable or ui:repeat?
...ved for the form submit request. Best is to put the bean in the view scope by @ViewScoped.
You can even pass the entire item object:
<h:commandLink action="#{bean.insert(item)}" value="insert" />
with:
public void insert(Item item) {
// ...
}
On Servlet 2.5 containers, this is also p...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
...is:
WITH cte AS (
SELECT[foo], [bar],
row_number() OVER(PARTITION BY foo, bar ORDER BY baz) AS [rn]
FROM TABLE
)
DELETE cte WHERE [rn] > 1
Play around with it and see what you get.
(Edit: In an attempt to be helpful, someone edited the ORDER BY clause within the CTE. To be clear, yo...
How do I find duplicate values in a table in Oracle?
...
Aggregate the column by COUNT, then use a HAVING clause to find values that appear greater than one time.
SELECT column_name, COUNT(column_name)
FROM table_name
GROUP BY column_name
HAVING COUNT(column_name) > 1;
...
How to create a date and time picker in Android? [closed]
...I think this response should be updated. The DateSlider library referenced by Rabi all the way below seems to be perfect for this.
– Stephan Branczyk
Aug 7 '11 at 21:09
...
Is there a MySQL option/feature to track history of changes to records?
...on. Whilst you can, just about, reconstruct the state of the database just by looking at audit tables, it's hard and error prone, and for any complicated database logic, it becomes unwieldy. For instance, if the business wants to know "find the addresses of the letters we should have sent to custome...
Objective-C: difference between id and void *
...ng called has not been declared in any of the @interface declarations seen by the compiler.
Thus, one should never refer to an object as a void *. Similarly, one should avoid using an id typed variable to refer to an object. Use the most specific class typed reference you can. Even NSObject *...
Converting an array of objects to ActiveRecord::Relation
...lizarHristov That's because it's now a relation, which can only be ordered by a column, and not any way you want. Relations are faster to handle large data sets, and there will be some trade-offs.
– Marco Prins
Mar 17 '15 at 9:45
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