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What is Normalisation (or Normalization)?
...he other, which is data corruption. The problem is solved by splitting the table in two, and creating a primary key/foreign key relationship:
UserId(FK) | Car UserId(PK) | UserName
--------------------- -----------------
1 | Toyota 1 | John
2 ...
What is the relative performance difference of if/else versus switch statement in Java?
...ere are more than two if/else blocks glued together or its size is unpredictable, then you may highly consider a switch statement.
Alternatively, you can also grab Polymorphism. First create some interface:
public interface Action {
void execute(String input);
}
And get hold of all implemen...
Building a notification system [closed]
...this topic is already quite old, however i'm a bit puzzled about the first table, what excactly is the purpose of this table? what is the advantage of having this as a separate table versus putting the userID in the notification_object table? In other words when will you create a new entry in notifi...
In Postgresql, force unique on combination of two columns
I would like to set up a table in PostgreSQL such that two columns together must be unique. There can be multiple values of either value, so long as there are not two that share both.
...
Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
... that SQL Server can access the data from indexes rather than querying the table data.
Here's a post I wrote about it: The real reason select queries are bad index coverage
It's also less fragile to change, since any code that consumes the data will be getting the same data structure regardless...
Which is more preferable to use: lambda functions or nested functions ('def')?
...with def. The difference is due to def creating a name entry in the locals table. The resulting function has the same execution speed.
Readability:
Lambda functions are somewhat less readable for most Python users, but also much more concise in some circumstances. Consider converting from using ...
Convert generic List/Enumerable to DataTable?
...te using FastMember from NuGet:
IEnumerable<SomeType> data = ...
DataTable table = new DataTable();
using(var reader = ObjectReader.Create(data)) {
table.Load(reader);
}
This uses FastMember's meta-programming API for maximum performance. If you want to restrict it to particular members (...
assertEquals vs. assertEqual in python
...ase methods had one or more aliases that are now deprecated. The following table lists the correct names along with their deprecated aliases:
Method Name | Deprecated alias | Deprecated alias
--------------+------------------+-----------------
assertEqual() | failUnlessEqual | assertEquals
...
...
Nested Models in Backbone.js, how to approach
...
Of course, if you want to go as far as saving the nested model in its own table. This wouldn't be sufficient. But in the case of reading and saving the object as a whole, this solution should suffice.
share
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Is it possible to insert multiple rows at a time in an SQLite database?
...t syntax. To make it perfectly clear, the OPs MySQL example:
INSERT INTO 'tablename' ('column1', 'column2') VALUES
('data1', 'data2'),
('data1', 'data2'),
('data1', 'data2'),
('data1', 'data2');
This can be recast into SQLite as:
INSERT INTO 'tablename'
SELECT 'data1' AS 'co...