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Many-to-many relationship with the same model in rails?
...ociations from irb, and looking at the SQL that Rails generates in the log file. You'll find something like the following:
SELECT * FROM "posts"
INNER JOIN "post_connections" ON "posts".id = "post_connections".post_b_id
WHERE ("post_connections".post_a_id = 1 )
To make the association bi-directio...
java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
...not used it) is log4jdbc. You then need to do some simple analysis on this file to see which executes don't have a corresponding close. Counting the open and closes should highlight if there is a potential problem
Monitoring the database. Monitor your running application using the tools such as th...
How are people unit testing with Entity Framework 6, should you bother?
...rk into the Test Project.
2- Put the connection string into the app.config file of Test Project.
3- Reference the dll System.Transactions in Test Project.
The unique side effect is that identity seed will increment when trying to insert, even when the transaction is aborted. But since the tests are...
Java HashMap performance optimization / alternative
...done simpler as follows: int result = a[0]; result = result * 52 + a[1]; //etc.
– rsp
Nov 19 '09 at 16:20
I agree that...
glVertexAttribPointer clarification
... attributes are just the new way of defining vertices, texcoords, normals, etc. for drawing. VAOs store state. I'm first going to explain how drawing works with vertex attributes, then explain how you can cut down the number of method calls with VAOs:
You must enable an attribute before you can us...
Biggest advantage to using ASP.Net MVC vs web forms
... there is an abundance of information with regards to questions, problems, etc. Offers more third-party control - need to consider your existing toolkits.
ASP.NET MVC:
Separation of concerns (SoC)
• From a technical standpoint, the organization of code within MVC is very clean, organized an...
How should I have explained the difference between an Interface and an Abstract class?
...yment class. Payment can be made in many ways, such as PayPal, credit card etc. So we normally take Payment as our interface which contains a makePayment() method and CreditCard and PayPal are the two implementation classes.
public interface Payment
{
void makePayment();//by default it is a abs...
What is the difference between the Data Mapper, Table Data Gateway (Gateway), Data Access Object (DA
...thods like insert, update, delete and in table data gateway you will find getcustomerbyId, getcustomerbyName, etc.
Data transfer object differs from the above two patterns, mainly because it is a distribution pattern and not a data source pattern as above two patterns. Use it mainly when you are wo...
Why does Python code run faster in a function?
... technical detail about this optimization, here's a quote from the ceval.c file (the "engine" of Python's virtual machine):
Some opcodes tend to come in pairs thus making it possible to
predict the second code when the first is run. For example,
GET_ITER is often followed by FOR_ITER. And...
Why are mutable structs “evil”?
...w and then - especially with your Business Model, where you want streaming etc. to work smoothly with existing solutions. I wrote an article on how to work with mutable AND immutable data, solving most issues around mutability (I hope): rickyhelgesson.wordpress.com/2012/07/17/…
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