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Python list directory, subdirectory, and files
...ncatenate the directory and file name:
for path, subdirs, files in os.walk(root):
for name in files:
print os.path.join(path, name)
Note the usage of path and not root in the concatenation, since using root would be incorrect.
In Python 3.4, the pathlib module was added for easier path...
NoSQL - MongoDB vs CouchDB [closed]
...ch, filling up disks.
For example: For most things that you would do with MySQL or PostgreSQL, but having predefined columns really holds you back.
CouchDB (1.2)
Written in: Erlang
Main point: DB consistency, ease of use
License: Apache
Protocol: HTTP/REST
Bi-directional (!) replication,
continu...
What is the difference between MySQL Server and MySQL Client
...nstall both but what are the differences between the client and server for MySQL.
3 Answers
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Swapping column values in MySQL
I have a MySQL table with coordinates, the column names are X and Y. Now I want to swap the column values in this table, so that X becomes Y and Y becomes X. The most apparent solution would be renaming the columns, but I don't want to make structure changes since I don't necessarily have permission...
Find most frequent value in SQL column
...+1 for using standard SQL that will work in any database (whereas LIMIT is MySQL specific, TOP is SQL Server specific).
– Dylan Smith
Jul 20 '18 at 14:46
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How do I calculate square root in Python?
...valuate to 0.
And for the record, the preferred way to calculate a square root is this:
import math
math.sqrt(x)
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XAMPP - MySQL shutdown unexpectedly
When I open XAMPP and click start MySQL button and it gives me an error.
I had started it just before, but now it isn't working.
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SQL command to display history of queries
I would like to display my executed sql command history in my MYSQL Query Browser. What is the sql statement for displaying history?
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PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
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To answer your concerns:
MySQL >= 5.1.17 (or >= 5.1.21 for the PREPARE and EXECUTE statements) can use prepared statements in the query cache. So your version of MySQL+PHP can use prepared statements with the query cache. However, make careful ...
CHECK constraint in MySQL is not working
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MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
T...