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How to update column with null value
...Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
| some_id | your_column |
+---------+-------------+
| 1 | NULL |
+---------+-------------+
1 row in set (0.00 sec)
...
How to set auto increment primary key in PostgreSQL?
...able(moobars,foobars) values('worldwide interblag','2012-05-02')
Step 3, select * from your table:
el@voyager$ psql -U pgadmin -d kurz_prod -c "select * from epictable"
Step 4, interpret the output:
mytable_key | moobars | foobars
-------------+-----------------------+------...
How to select the row with the maximum value in each group
In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
...
How to call Android contacts list?
...TION_PICK on the People.CONTENT_URI, then return to this Activity when the selection is made (or canceled).
startActivityForResult(intent, PICK_CONTACT);
3. Listening for the Result
Also in your Activity, override the onActivityResult method to listen for the return from the 'select a contact' A...
pycharm convert tabs to spaces automatically
...
Change the code style to use spaces instead of tabs:
Then select a folder you want to convert in the Project View and use Code | Reformat Code.
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Why am I getting “Cannot Connect to Server - A network-related or instance-specific error”?
...ation
Click on Surface Area Configuration for Services and Connections
Select the instance that is having a problem > Database Engine > Remote Connections
Enable local and remote connections
Restart instance
You may need to create an exception on the firewall for the SQL Server ...
Working copy locked error in tortoise svn while committing
...em. I did this lots of time... :)
Note. Make sure "Break locks" option is selected in the Cleanup dialog.
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Filter data.frame rows by a logical condition
...
To select rows according to one 'cell_type' (e.g. 'hesc'), use ==:
expr[expr$cell_type == "hesc", ]
To select rows according to two or more different 'cell_type', (e.g. either 'hesc' or 'bj fibroblast'), use %in%:
expr[expr$...
Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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best way to add license section to iOS settings bundle
...save it to the root of your project.
Expand the Settings.bundle group and select Root.plist. You will need to add a new section where its key will be Preference Items of type Array. Add the following information:
The Filename key points to the plist that was created by this script. You can cha...