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Database Structure for Tree Data Structure
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Have a look at Managing Hierarchical Data in MySQL. It discusses two approaches for storing and managing hierarchical (tree-like) data in a relational database.
The first approach is the adjacency list model, which is what you essentially describe: having a foreign key...
Relative paths in Python
...ipt that was used to invoke the Python interpreter.
Use this path as the root folder from which you apply your relative path
>>> import sys
>>> import os.path
>>> sys.path[0]
'C:\\Python25\\Lib\\idlelib'
>>> os.path.relpath(sys.path[0], "path_to_libs") # if you...
How to copy from CSV file to PostgreSQL table with headers in CSV file?
...because it uses native DB import commands. It supports Postgres as well as MYSQL and MS SQL.
import pandas as pd
df = pd.read_csv('table.csv')
uri_psql = 'postgresql+psycopg2://usr:pwd@localhost/db'
d6tstack.utils.pd_to_psql(df, uri_psql, 'table')
It is also useful for importing multiple CSVs, so...
How to join components of a path when you are constructing a URL in Python
... begins with a slash which signifies that it already begins at the website root.
On Python 2, you have to do
from urlparse import urljoin
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Update all values of a column to lowercase
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See http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_lower
UPDATE table_name SET tag = LOWER(tag)
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can we use xpath with BeautifulSoup?
... One warning: I've noticed if there is something outside the root (like a \n outside the outer <html> tags), then referencing xpaths by the root will not work, you have to use relative xpaths. lxml.de/xpathxslt.html
– wordsforthewise
Sep 6 '...
ASP.NET 2.0 - How to use app_offline.htm
I've read about the app_offline.htm file which can be placed within the root of a .NET 2.0 application which will in essence shut down the application and disable any other pages from being requested.
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Nginx 403 error: directory index of [folder] is forbidden
... Throwing the error mentioned by OP.
try_files $uri $uri/ means, from the root directory, try the file pointed by the uri, if that does not exists, try a directory instead (hence the /). When nginx access a directory, it tries to index it and return the list of files inside it to the browser/client...
How do you organize your version control repository?
... in source control, as long as you preserve the structure from the project root directory on down
-- build each project anywhere on any machine, with minimum risk and minimum preparation
-- build each project completely stand-alone, as long as you have access to its binary dependencies (local "lib...
Why should I capitalize my SQL keywords? [duplicate]
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So does MySQL, and for good and for bad (mostly bad:-), many developers first exposure to SQL is through MySQL.
– Paul Tomblin
Mar 4 '09 at 13:41
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