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Display names of all constraints for a table in Oracle SQL
...
You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...
Package objects
...
Normally you would put your package object in a separate file called package.scala in the package that it corresponds to. You can also use the nested package syntax but that is quite unusual.
The main use case for package object...
How to use Global Variables in C#?
...er the behavior of static variables declared inside, but it doesn't look really useful.
– Tommaso Belluzzo
Feb 2 at 18:01
...
How to create a density plot in matplotlib?
...with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the function covariance_factor of the gaussian_kde class. First, here is what you get without changing that function:
However, if I use the following code:
import...
Notification click: activity already open
...current task, then instead of launching a new instance of that
activity, all of the other activities on top of it will be closed and
this Intent will be delivered to the (now on top) old activity as a
new Intent.
For example, consider a task consisting of the activities: A, B, C, D.
If...
How do I get class name in PHP?
.... I found this out by trying to access the ::class property(?) of a dynamically generated class and getting the following error: Dynamic class names are not allowed in compile-time ::class fetch. See this answer for more details. I also found this note from the docs helpful.
–...
Define make variable at rule execution time
...r are evaluated. In order to create the directory only when out.tar is actually fired, you need to move the directory creation down into the steps:
out.tar :
$(eval TMP := $(shell mktemp -d))
@echo hi $(TMP)/hi.txt
tar -C $(TMP) cf $@ .
rm -rf $(TMP)
The eval function evaluates a...
Creating a JSON response using Django and Python
...JSON content.
import json
from django.http import HttpResponse
response_data = {}
response_data['result'] = 'error'
response_data['message'] = 'Some error message'
Pre-Django 1.7 you'd return it like this:
return HttpResponse(json.dumps(response_data), content_type="application/json")
For D...
Add a property to a JavaScript object using a variable as the name?
...out modifying but it's referenced by other questions that are about dynamically creating objects and so I ended up here and happily benefited from this answer.
– Oliver Lloyd
Oct 29 '16 at 17:40
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How do you remove duplicates from a list whilst preserving order?
...n seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule t...