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Is there a JSON equivalent of XQuery/XPath?
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The site linked here provides for Javascript and PHP. If you need a Java implementation, there’s one here: code.google.com/p/json-path
– Matthias Ronge
Nov 16 '12 at 7:20
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Using an RDBMS as event sourcing storage
...ifically with SQL, we found that performance really became a bottleneck if indexes and partitions weren't adequately used. Remember events will needs to be streamed in reverse order if you are using snapshots. We tried a few different indexes and found that in practise, some additional indexes were ...
SQLite: How do I save the result of a query as a CSV file?
...')
df = pd.read_sql('SELECT * from orders', conn)
df.to_csv('orders.csv', index = False)
You can customize the query to only export part of the sqlite table to the CSV file.
You can also run a single command to export all sqlite tables to CSV files:
for table in c.execute("SELECT name FROM sqlite_...
How to extract the decision rules from scikit-learn decision-tree?
...ent, np.argmax(tree_.value[node][0])) for the function to return the class index.
– soupault
Oct 19 '17 at 9:56
2
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Get unique values from a list in python [duplicate]
...ch, 2019
And a 3rd solution, which is a neat one, but kind of slow since .index is O(n).
mylist = [u'nowplaying', u'PBS', u'PBS', u'nowplaying', u'job', u'debate', u'thenandnow']
unique = [x for i, x in enumerate(mylist) if i == mylist.index(x)]
UPDATE - Oct, 2016
Another solution with reduce, ...
How to add a primary key to a MySQL table?
... goods to goods_old;
create new table with primary key and all necessary indexes:
create table goods (
id int(10) unsigned not null AUTO_INCREMENT
... other columns ...
primary key (id)
);
move all data from the old table into new, disabling keys and indexes to speed up copying:
-...
How to randomly pick an element from an array
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You can use the Random generator to generate a random index and return the element at that index:
//initialization
Random generator = new Random();
int randomIndex = generator.nextInt(myArray.length);
return myArray[randomIndex];
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How can I access the MySQL command line with XAMPP for Windows?
How can I access the MySQL command line with XAMPP for Windows?
15 Answers
15
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Concurrent HashSet in .NET Framework?
...> doesn't officially concurrent access, even for reading operations.
I quote the code of the linked post (originally written by Ben Mosher).
using System;
using System.Collections.Generic;
using System.Threading;
namespace BlahBlah.Utilities
{
public class ConcurrentHashSet<T> : IDis...
Best way to format integer as string with leading zeros? [duplicate]
...of digits ($cnt).
What the best way to translate this simple function from PHP to Python:
10 Answers
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