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How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...
What's the idiomatic syntax for prepending to a short python list?
...67281929729506
>>> min(timeit.repeat(list_slice_insert))
2.5210217320127413
>>> min(timeit.repeat(list_add))
2.0641671380144544
>>> min(timeit.repeat(deque_appendleft))
1.5863927800091915
>>> min(timeit.repeat(deque_extendleft))
0.5352169770048931
The deque is m...
How to change the name of a Django app?
...ls.py , 'manage.py' , and settings.py files.
Edit the database table django_content_type with the following command: UPDATE django_content_type SET app_label='<NewAppName>' WHERE app_label='<OldAppName>'
Also if you have models, you will have to rename the model tables. For postgres use...
How to create composite primary key in SQL Server 2008
...name
– longhairedsi
Dec 6 '12 at 14:32
14
Not quite true. Both create "named constraints". It's j...
How to prevent blank xmlns attributes in output from .NET's XmlDocument?
...t back.
– user1228
Sep 25 '08 at 18:32
@W. Craig Trader - can't say I've encountered that as a problem. Example?
...
How to show android checkbox at right side?
...
– Monica Aspiras Labbao
Aug 24 '16 at 2:32
How to detect my browser version and operating system using JavaScript?
...
mplungjan
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answered Jun 27 '12 at 5:00
Himanshu JansariH...
“ImportError: No module named” when trying to run Python script
...d the folder in which you told the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting).
The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys....
How do you set a default value for a MySQL Datetime column?
...ut you can do it with TIMESTAMP:
mysql> create table test (str varchar(32), ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP);
Query OK, 0 rows affected (0.00 sec)
mysql> desc test;
+-------+-------------+------+-----+-------------------+-------+
| Field | Type | Null | Key | Default ...
How to implement has_many :through relationships with Mongoid and mongodb?
... |
edited May 4 '15 at 17:32
answered May 1 '13 at 1:09
Ste...