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Improve INSERT-per-second performance of SQLite
...more memory will be used for your database.
If you have indices, consider calling CREATE INDEX after doing all your inserts. This is significantly faster than creating the index and then doing your inserts.
You have to be quite careful if you have concurrent access to SQLite, as the whole database i...
How to increment a datetime by one day?
...
All of the current answers are wrong in some cases as they do not consider that timezones change their offset relative to UTC. So in some cases adding 24h is different from adding a calendar day.
Proposed solution
The follo...
How to toggle a value in Python
...; toggle()
'blue'
Note that in Python 3 the next() method was changed to __next__(), so the first line would be now written as toggle = itertools.cycle(['red', 'green', 'blue']).__next__
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How do I load a file from resource folder?
...e examples of how that class is used:
src\main\java\com\company\test\YourCallingClass.java
src\main\java\com\opensymphony\xwork2\util\ClassLoaderUtil.java
src\main\resources\test.csv
// java.net.URL
URL url = ClassLoaderUtil.getResource("test.csv", YourCallingClass.class);
Path path = Paths.get(ur...
GraphViz - How to connect subgraphs?
...luster, that can be linked to even if the cluster is empty otherwise. DUMMY_0 [shape=point style=invis]
– DevSolar
Jun 25 '12 at 7:36
2
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Ruby on Rails - Import Data from a CSV file
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The smarter_csv gem was specifically created for this use-case: to read data from CSV file and quickly create database entries.
require 'smarter_csv'
options = {}
SmarterCSV.process('input_file.csv', options) do |chunk|
chunk.each do |data_hash|
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What is a stored procedure?
... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CRE...
How can I store my users' passwords safely?
...tials';
}
(In case you are still using legacy 5.3.7 or newer you can install ircmaxell/password_compat to have access to the build-in functions)
Improving upon salted hashes: add pepper
If you want extra security, the security folks now (2017) recommend adding a 'pepper' to the (automatically)...
Creating an empty Pandas DataFrame, then filling it?
...utocompletion), but that works with strings as date format, right? The overall approach works though (I changed index to something else).
– Matthias Kauer
Dec 15 '12 at 8:42
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How to log PostgreSQL queries?
How to enable logging of all SQL executed by PostgreSQL 8.3?
10 Answers
10
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