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MySQL: @variable vs. variable. What's the difference?
...
MySQL has a concept of user-defined variables.
They are loosely typed variables that may be initialized somewhere in a session and keep their value until the session ends.
They are prepended with an @ sign, like this: @var
You ...
MVC Razor view nested foreach's model
...w it does its work is important here.
(Note other frameworks like LINQ to SQL do similar things by walking an expression tree and building a different grammar, that this case a SQL query)
How does the Model Binder work?
So once you get that, we have to briefly talk about the model binder. When th...
How to append rows to an R data frame
...operation and couple it with manually doubling the table when needed.
Use RSQLite and append to the table held in memory.
data.frame's own ability to grow and use custom environment (which has reference semantics) to store the data.frame so it will not be copied on return.
Here is a test of all th...
What is the proper way to re-attach detached objects in Hibernate?
...alse(book == _book);
});
And Hibernate is going to execute the following SQL statements:
SELECT
b.id,
b.author AS author2_0_,
b.isbn AS isbn3_0_,
b.title AS title4_0_
FROM
book b
WHERE
b.id = 1
-- Merging the Book entity
UPDATE
book
SET
author = 'Vlad Mihalcea',
...
Local Storage vs Cookies
...small in size, cookies are sent with every HTTP request Limited size
(4KB)
SQL injection can be performed from a cookie
Local storage
Pros
Support by most modern browsers
Persistent data that is stored directly in the browser
Same-origin rules apply to local storage data
Is not sent with every...
How serious is this new ASP.NET security vulnerability and how can I workaround it?
...information in a database connection string, or even link to an automouted sql-express database which you don't want someone to get hold of. But if you are following best practice you use Protected Configuration to encrypt all sensitive data in your web.config.
Links to references
Read Microsoft's...
File name? Path name? Base name? Naming standard for pieces of a path
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Consider the path C:\Documents and Settings\All Users\Application Data\s.sql.
C:\Documents and Settings\All Users\Application Data\s.sql is the full path (which is a file name)
C:\Documents and Settings\All Users\Application Data\ is the directory name.
Now consider the path C:\Documents and S...
Clustered vs Non-Clustered
My lower level knowledge of SQL (Server 2008) is limited, and is now being challanged by our DBAs. Let me explain (I have mentioned obvious statements in the hope that I am right, but if you see something wrong, please tell me) the scenario:
...
DateTime vs DateTimeOffset
... DateTimeOffset in C#, then you should persist that to a DATETIMEOFFSET in SQL Server. DATETIME2 or just DATETIME (depending on the range required) are fine for regular DateTime values. Yes - you can resolve a local time from any pairing of timezone + dto or utc. The difference is - do you always...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
...which only has the identifier set. If you access the Proxy, the associated SQL statement will be triggered as long as the EntityManager is still open.
However, in this case, we don’t need to access the entity Proxy. We only want to propagate the Foreign Key to the underlying table record so loadi...