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Database Design for Tagging
...e fine and scale out assuming the right b-tree indexes exist on the middle table
– Adam Musch
Feb 24 '10 at 16:41
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Why do we always prefer using parameters in SQL statements?
...ommands against your database, including deleting it If they wrote 0; Drop Table employee:
SELECT empSalary from employee where salary = 0; Drop Table employee
The table employee would then be deleted.
In your case, it looks like you're using .NET. Using parameters is as easy as:
C#
string s...
MYSQL Dump only certain rows
...t dumps everything. How can I get mysqldump to only dump certain rows of a table?
3 Answers
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What are the disadvantages of using persistent connection in PDO
...tion die when the script terminates abnormally.
If the dead script locked tables, those tables will remain locked until the connection dies or the next script that gets the connection unlocks the tables itself.
If the dead script was in the middle of a transaction, that can block a multitude of ta...
Return rows in random order [duplicate]
Is it possible to write SQL query that returns table rows in random order every time the query run?
6 Answers
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How to implement the activity stream in a social network
...rowse far back in time (if you even offer this)
I use a plain old MySQL table for dealing with about 15 million activities.
It looks something like this:
id
user_id (int)
activity_type (tinyint)
source_id (int)
parent_id (int)
parent_type (tinyint)
time (...
What are file descriptors, explained in simple terms?
...file in operating system.
If your process opens 10 files then your Process table will have 10 entries for file descriptors.
Similarly when you open a network socket, it is also represented by an integer and it is called Socket Descriptor.
I hope you understand.
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How to make an inline-block element fill the remainder of the line?
...e using CSS and two inline-block (or whatever) DIV tags instead of using a table?
7 Answers
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Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...ngle context per app can be expensive if the application has many entities/tables. Thus depending on the schema, it might also make sense to have multiple contexts.
– DarthVader
May 13 '13 at 7:04
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What is the optimal length for user password salt? [closed]
...ices for how long the salt should be? I'll be storing the salt in my user table, so I would like the best tradeoff between storage size and security. Is a random 10 character salt enough? Or do I need something longer?
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