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Function to Calculate Median in SQL Server
... the 7 years since, but personally I wouldn't use this function on a large table until I verified its performance vs. other solutions.
ORIGINAL 2009 POST IS BELOW:
There are lots of ways to do this, with dramatically varying performance. Here's one particularly well-optimized solution, from Median...
map vs. hash_map in C++
....
hash_map (unordered_map in TR1 and Boost; use those instead) use a hash table where the key is hashed to a slot in the table and the value is stored in a list tied to that key.
map is implemented as a balanced binary search tree (usually a red/black tree).
An unordered_map should give slightly ...
When NOT to use Cassandra?
...zing log data, or any place where scanning huge, two-dimensional join-less tables is a requirement. Redis is built to provide In-Memory search for varieties of data structures like trees, queues, linked lists, etc and can be a good fit for making real-time leaderboards, pub-sub kind of system. Simil...
On duplicate key ignore? [duplicate]
...).
Instead, since in your example tag is the unique key, use:
INSERT INTO table_tags (tag) VALUES ('tag_a'),('tab_b'),('tag_c') ON DUPLICATE KEY UPDATE tag=tag;
on duplicate key produces:
Query OK, 0 rows affected (0.07 sec)
...
Javascript. Assign array values to multiple variables? [duplicate]
...t in languages such as Perl and Python.
Unfortunately, according to this table of versions, JavaScript 1.7 has not been implemented in Chrome. But it should be there in:
FireFox 2.0+
IE 9
Opera 11.50.
Try it for yourself in this jsfiddle: http://jsfiddle.net/uBReg/
I tested this on Chrome (f...
Is there a way to “limit” the result with ELOQUENT ORM of Laravel?
...
Also, we can use it following ways
To get only first
$cat_details = DB::table('an_category')->where('slug', 'people')->first();
To get by limit and offset
$top_articles = DB::table('an_pages')->where('status',1)->limit(30)->offset(0)->orderBy('id', 'DESC')->get();
$remaining...
What does multicore assembly language look like?
.... All that's needed is software support for each thread to set up its own tables and messaging queues. The OS uses those to do the actual multi-threaded scheduling.
As far as the actual assembly is concerned, as Nicholas wrote, there's no difference between the assemblies for a single threaded or...
python-pandas and databases like mysql
...pass@host:port/schema', echo=False)
f = pd.read_sql_query('SELECT * FROM mytable', engine, index_col = 'ID')
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Heatmap in matplotlib with pcolor?
...s(np.arange(nba_sort.shape[1]) + 0.5, minor=False)
# want a more natural, table-like display
ax.invert_yaxis()
ax.xaxis.tick_top()
# Set the labels
# label source:https://en.wikipedia.org/wiki/Basketball_statistics
labels = [
'Games', 'Minutes', 'Points', 'Field goals made', 'Field goal attem...
Deprecated: mysql_connect()
...tical with the old way:
<?php
// Old way
mysql_query('CREATE TEMPORARY TABLE `table`', $connection);
// New way
mysqli_query($connection, 'CREATE TEMPORARY TABLE `table`');
Turn off all deprecated warnings including them from mysql_*:
<?php
error_reporting(E_ALL ^ E_DEPRECATED);
The Exac...