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Convert text into number in MySQL query
Is it possible to convert text into number within MySQL query? I have a column with an identifier that consists a name and a number in the format of "name-number". The column has VARCHAR type. I want to sort the rows according the number (rows with the same name) but the column is sorted according d...
Ordering by specific field value first
...
There's also the MySQL FIELD function.
If you want complete sorting for all possible values:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")
If you only care that "core" is first and the other values ...
Quick and easy file dialog in Python?
... show only the dialog without any other GUI elements, you have to hide the root window using the withdraw method:
import tkinter as tk
from tkinter import filedialog
root = tk.Tk()
root.withdraw()
file_path = filedialog.askopenfilename()
Python 2 variant:
import Tkinter, tkFileDialog
root = T...
MySQL remove all whitespaces from the entire column
...UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\n', '')
http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace
To remove first and last space(s) of column :
UPDATE `table` SET `col_name` = TRIM(`col_name`)
http://dev.mysql.com/doc/refman/5.0/en/string-functions.htm...
JRE 1.7 - java version - returns: java/lang/NoClassDefFoundError: java/lang/Object
...-r -v rt.pack rt.jar
To recursively unpack all .pack files, from the JRE root run:
for /r %f in (*.pack) do "%JAVA_HOME%\bin\unpack200.exe" -r -q "%f" "%~pf%~nf.jar"
*nix
To unpack one .pack file (for example rt.pack), run:
/usr/bin/unpack200 -r -v rt.pack rt.jar
To recursively unpack all ....
Which is faster: multiple single INSERTs or one multiple-row INSERT?
I am trying to optimize one part of my code that inserts data into MySQL. Should I chain INSERTs to make one huge multiple-row INSERT or are multiple separate INSERTs faster?
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View's SELECT contains a subquery in the FROM clause
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As per documentation:
MySQL Docs
The SELECT statement cannot contain a subquery in the FROM clause.
Your workaround would be to create a view for each of your subqueries.
Then access those views from within your view view_credit_status
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Convert a Git folder to a submodule retrospectively?
...ven though I have tested this successfully)!
0. Preparation
Variables
# Root directory where repo-org lives
# and a temporary location for git filter-branch
root="$PWD"
temp='/dev/shm/tmp'
# The old repository and the subdirectory we'd like to extract
repo_old="$root/repo-old"
repo_old_directory...
How can I see the specific value of the sql_mode?
There are some sql_mode values in MySQL:
2 Answers
2
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How to log PostgreSQL queries?
... that mean PostgreSQL can't enable logging unless I restart the server? In MySQL, it is as simple as "SET GLOBAL general_log = 'ON';"
– Antony
Dec 7 '11 at 22:41
7
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