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What is the most efficient/elegant way to parse a flat table into a tree?
..., we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive que...
Difference Between Select and SelectMany
I've been searching the difference between Select and SelectMany but I haven't been able to find a suitable answer. I need to learn the difference when using LINQ To SQL but all I've found are standard array examples.
...
How do I make a batch file terminate upon encountering an error?
I have a batch file that's calling the same executable over and over with different parameters. How do I make it terminate immediately if one of the calls returns an error code of any level?
...
Difference between JSONObject and JSONArray
...
When you are working with JSON data in Android, you would use JSONArray to parse JSON which starts with the array brackets. Arrays in JSON are used to organize a collection of related items (Which could be JSON objects).
For example: [{"name":"item 1"},{"name": "...
When to use UICollectionView instead of UITableView?
...ionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath and in UITableViewDelegate:
`-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath`
You get the selected row instead of the item, so for creating grid or modified items, using UICollect...
Python string prints as [u'String']
...duces Unicode. So you need to convert the list to a single unicode string, and then convert that to ASCII.
I don't know exaxtly how you got the one-element lists; the contents member would be a list of strings and tags, which is apparently not what you have. Assuming that you really always get a li...
How do I create a directory from within Emacs?
How exactly can I create a new directory using Emacs? What commands do I use? (If possible, please provide an example)
6 An...
jQuery Validate Plugin - Trigger validation of single field
...y be pre-populated via facebook connect. Once a user connects, their name and email are automatically filled in. The problem is that this doesn't trigger the remote validation to check if the email already exists.
...
Import Error: No module named numpy
... answered Feb 18 '16 at 8:51
Andrei Madalin ButnaruAndrei Madalin Butnaru
2,92622 gold badges99 silver badges66 bronze badges
...
Add list to set?
... hashable objects. The objects have to be hashable so that finding, adding and removing elements can be done faster than looking at each individual element every time you perform these operations. The specific algorithms used are explained in the Wikipedia article. Pythons hashing algorithms are exp...