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Is an index needed for a primary key in SQLite?
When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all t...
Naming convention for unique constraint
...rimary key and foreign key have commonly used and obvious conventions ( PK_Table and FK_Table_ReferencedTable , respectively). The IX_Table_Column naming for indexes is also fairly standard.
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UITableViewCell subview disappears when cell is selected
I'm implementing a color-chooser table view where the user can select amongst, say, 10 colors (depends on the product). The user can also select other options (like hard drive capacity, ...).
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How to serialize SqlAlchemy result to JSON?
...s_dict(self):
return {c.name: getattr(self, c.name) for c in self.__table__.columns}
And then you use User.as_dict() to serialize your object.
As explained in Convert sqlalchemy row object to python dict
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The relationship could not be changed because one or more of the foreign-key properties is non-nulla
...ing this issue is because of how you've set your primary key in your child table. It should be composite, but it's not. So, Entity Framework sees this association as aggregation, which means, when you remove or clear the child objects, it's not going to delete the child records. It'll simply remove ...
How to find out the MySQL root password
... did the following:
sudo service mysql stop
sudo mysqld_safe --skip-grant-tables --skip-syslog --skip-networking
Then run mysql in a new terminal:
mysql -u root
And run the following queries to change the password:
UPDATE mysql.user SET authentication_string=PASSWORD('password') WHERE User='r...
What are the options for storing hierarchical data in a relational database? [closed]
...useful for managing hierarchical data:
the HierarchyId data type.
common table expressions, using the with keyword.
Have a look at "Model Your Data Hierarchies With SQL Server 2008" by Kent Tegels on MSDN for starts. See also my own question: Recursive same-table query in SQL Server 2008
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How to prevent long words from breaking my div?
Ever since switching from TABLE-layout to DIV-layout, one common problem remains:
26 Answers
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How to add 'ON DELETE CASCADE' in ALTER TABLE statement
I have a foreign key constraint in my table, I want to add ON DELETE CASCADE to it.
9 Answers
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UITableView load more when scrolling to bottom like Facebook application
...eloping an application that uses SQLite. I want to show a list of users (UITableView) using a paginating mechanism. Could any one please tell me how to load more data in my list when the user scrolls to the end of the list (like on home page on Facebook application)?
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