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What is so bad about singletons? [closed]
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I disagree with you. Since comments are allowed only 600 chars, I have written a Blog Post to comment on this, please see the link below. jorudolph.wordpress.com/2009/11/22/singleton-considerations
– Johannes Rudolph
Nov 22 '09 at 14:35
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Moving Files into a Real Folder in Xcode
... Xcode should now be red (that's OK!).
From the Identity and Type manager, select the Group in Xcode that you want to relocate, then click the folder icon from the info pane:
In the Finder selection dialog, locate the equivalent new folder you created for this group in step 2. All the files insid...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...and sequences too. Here's what I did:
Tables:
for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do psql -c "alter table \"$tbl\" owner to NEW_OWNER" YOUR_DB ; done
Sequences:
for tbl in `psql -qAt -c "select sequence_name from information_schem...
What are the uses for Cross Join?
...ly, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might c...
MySQL/SQL: Group by date only on a Datetime column
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Cast the datetime to a date, then GROUP BY using this syntax:
SELECT SUM(foo), DATE(mydate) FROM a_table GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY DateOnly;
Though I don't think...
How to select different app.config for several build configurations
...ctory. So if you had PatternPA.Test.Integration project and a Debug config selected, in the output folder after the build you will find a PatternPA.Test.Integration.dll.config file which was copied from Config\App.Debug.config and renamed afterwards.
These are some notes you can leave in the config...
What does SQL clause “GROUP BY 1” mean?
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SELECT account_id, open_emp_id
^^^^ ^^^^
1 2
FROM account
GROUP BY 1;
In above query GROUP BY 1 refers to the first column in select statement which is
account_id.
You also can speci...
Auto-expanding layout with Qt-Designer
...your widget/dialog/window (not the QVBoxLayout, but the parent widget) and select Lay Out -> Lay Out in a Grid from the bottom of the context-menu. The QVBoxLayout should now stretch to fit the window and will resize automatically when the entire window is resized.
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Database Diagram Support Objects cannot be Installed … no valid owner
...rator and this has also invalidated the current owner of the database.
If SELECT @@SERVERNAME; is not accurate (it should say DevPC), then in order to ensure that your server rename has taken hold within SQL Server, you may also want to issue the following:
EXEC sp_dropserver @server = N'old serve...
Retain precision with double in Java
... Types, Formats, and Values of the Java Language Specification.
The byte, char, int, long types are fixed-point numbers, which are exact representions of numbers. Unlike fixed point numbers, floating point numbers will some times (safe to assume "most of the time") not be able to return an exact re...