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MySQL INNER JOIN select only one row from second table
I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
Using Sinatra for larger projects via multiple files
...rb
main.rb
views/
layout.haml
login.haml
main.haml
config.ru
root = ::File.dirname(__FILE__)
require ::File.join( root, 'app' )
run MyApp.new
app.rb
# encoding: utf-8
require 'sinatra'
require 'haml'
class MyApp < Sinatra::Application
enable :sessions
configure :producti...
Count number of records returned by group by
... other databases to test it out on, and I'm not so familiar with T-Sql and MySQL syntax.
Also, I'm not entirely sure whether it's more efficient in the parser to do it this way, or whether everyone else's solution of nesting the select statement is better. But I find this one to be more elegant fr...
Where can I download english dictionary database in a text format? [closed]
... replace the deprecated syntax before running it against a 5.0+ version of MySQL
– Serguei Fedorov
Aug 16 '18 at 2:10
...
Get names of all keys in the collection
...p with $addToSet to get distinct keys across the entire collection. (Use $$ROOT for referencing the top level document.)
db.things.aggregate([
{"$project":{"arrayofkeyvalue":{"$objectToArray":"$$ROOT"}}},
{"$unwind":"$arrayofkeyvalue"},
{"$group":{"_id":null,"allkeys":{"$addToSet":"$arrayofkey...
Making Python loggers output all messages to stdout in addition to log file
...tput is handled by the handlers; just add a logging.StreamHandler() to the root logger.
Here's an example configuring a stream handler (using stdout instead of the default stderr) and adding it to the root logger:
import logging
import sys
root = logging.getLogger()
root.setLevel(logging.DEBUG)
...
Using GPU from a docker container?
...ocker
Find your nvidia devices
ls -la /dev | grep nvidia
crw-rw-rw- 1 root root 195, 0 Oct 25 19:37 nvidia0
crw-rw-rw- 1 root root 195, 255 Oct 25 19:37 nvidiactl
crw-rw-rw- 1 root root 251, 0 Oct 25 19:37 nvidia-uvm
Run Docker container with nvidia driver pre-installed
I've ...
How can I select rows with most recent timestamp for each key value?
...but here's more info if you wish, as well as other examples. It's from the MySQL manual, but above query works with every RDBMS (implementing the sql'92 standard).
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...
How do I include a file over 2 directories back?
... those links if you move your file, is:
require_once($_SERVER['DOCUMENT_ROOT'] . 'directory/directory/file');
DOCUMENT_ROOT is a server variable that represents the base directory that your code is located within.
share...
SQL statement to get column type
...
If you're using MySQL you could try
SHOW COLUMNS FROM `tbl_name`;
SHOW COLUMNS on dev.mysql.com
Otherwise you should be able to do
DESCRIBE `tbl_name`;
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