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Creation timestamp and last update timestamp with Hibernate and MySQL
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I would do this using a MySQL trigger so that even if the full entity is not saved or is modified by any external application or manual query, it'll still update these fields.
– Webnet
Jul 25 '13 at 12:09
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Automatically create an Enum based on values in a database lookup table?
...one also ; ), let the advanced students present it ...
So here is the DDL SQL for the table :
USE [ocms_dev]
GO
CREATE TABLE [dbo].[Role](
[RoleId] [int] IDENTITY(1,1) NOT NULL,
[RoleName] [varchar](50) NULL
) ON [PRIMARY]
So here is the console program producing the dll:
using S...
Why use 'virtual' for class properties in Entity Framework model definitions?
...rty allows you to denote it as the equivalent of a nullable Foreign Key in SQL. You do not HAVE to eagerly join every keyed table when performing a query, but when you need the information -- it becomes demand-driven.
I also mentioned nullable because many navigation properties are not relevant ...
how do you filter pandas dataframes by multiple columns
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However, I think the query syntax is neater and close to SQL, which makes it nice for data since. The chery on the cake is that it's faster with many rows :)
– csgroen
Aug 27 at 15:58
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How can I measure the speed of code written in PHP? [closed]
...ink the DB request doesn't take much time !
This should be profiled on the SQL server, not PHP, so...
Hope this is helpful :-)
Have fun !
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How do I automatically sort a has_many relationship in Rails?
...cantly slower (and use a lot more memory) than doing your ordering through SQL/ActiveRecord.
If you are doing something where adding a default order is cumbersome for some reason or you want to override your default in certain cases, it is trivial to specify it in the fetching action itself:
sort...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
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postgresql COUNT(DISTINCT …) very slow
I have a very simple SQL query:
4 Answers
4
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Prefer composition over inheritance?
...ng it to a relational database. It's really hard to map inheritance to the SQL model (you end up with all sorts of hacky workarounds, like creating columns that aren't always used, using views, etc). Some ORMLs try to deal with this, but it always gets complicated quickly. Composition can be easily ...
Creating temporary files in bash
...he file with their own version of the code (like replacing the commands or SQL queries depending on what is being stored).
You could use the following approach to create the temporary directory:
TMPDIR=".${0##*/}-$$" && mkdir -v "$TMPDIR"
or temporary file:
TMPFILE=".${0##*/}-$$" &...