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Use email address as primary key?
...ies with multiple joins.
If you store information about users in multiple tables, the foreign keys to the users table will be the e-mail address. That means that you store the e-mail address multiple times.
share
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Change a column type from Date to DateTime during ROR migration
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First in your terminal:
rails g migration change_date_format_in_my_table
Then in your migration file:
For Rails >= 3.2:
class ChangeDateFormatInMyTable < ActiveRecord::Migration
def up
change_column :my_table, :my_column, :datetime
end
def down
change_column :my_tabl...
Dynamic Sorting within SQL Stored Procedures
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This approach keeps the sortable columns from being duplicated twice in the order by, and is a little more readable IMO:
SELECT
s.*
FROM
(SELECT
CASE @SortCol1
WHEN 'Foo' THEN t.Foo
WHEN 'Bar' THEN t.Bar
ELSE null
END as ...
jQuery UI Sortable, then write order into a database
I want to use the jQuery UI sortable function to allow users to set an order and then on change, write it to the database and update it. Can someone write an example on how this would be done?
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How to change owner of PostgreSql database?
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@mArtinko5MB: Also impossible, ALTER TABLE doesn't DROP the table. Show us your SQL, something is badly broken in your statements.
– Frank Heikens
Oct 24 '13 at 13:24
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What are the most common SQL anti-patterns? [closed]
... will do.
DECLARE @LoopVar int
SET @LoopVar = (SELECT MIN(TheKey) FROM TheTable)
WHILE @LoopVar is not null
BEGIN
-- Do Stuff with current value of @LoopVar
...
--Ok, done, now get the next value
SET @LoopVar = (SELECT MIN(TheKey) FROM TheTable
WHERE @LoopVar < TheKey)
END
Number 3....
Working with huge files in VIM
...s a 300GB mysql dump and I wanted to get rid of the DROP and change CREATE TABLE to CREATE TABLE IF NOT EXISTS so didn't want to run two invocations of sed. I wrote this quick Ruby script to dupe the file with those changes:
#!/usr/bin/env ruby
matchers={
%q/^CREATE TABLE `foo`/ => %q/CREA...
Remove Primary Key in MySQL
I have the following table schema which maps user_customers to permissions on a live MySQL database:
12 Answers
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How do you rename a table in SQLite 3.0?
How do you rename a table in SQLite 3.0?
2 Answers
2
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'console' is undefined error for Internet Explorer
...le.debug
*
* Chrome 41.0.2272.118: debug,error,info,log,warn,dir,dirxml,table,trace,assert,count,markTimeline,profile,profileEnd,time,timeEnd,timeStamp,timeline,timelineEnd,group,groupCollapsed,groupEnd,clear
* Firefox 37.0.1: log,info,warn,error,exception,debug,table,trace,dir,group,groupCollap...