大约有 5,887 项符合查询结果（耗时：0.0188秒） [XML]
belongs_to through associations
...ter off caching the question_id on Choice and adding a unique index to the table (especially because validates_uniqueness_of is prone to race conditions).
If you're paranoid, add a custom validation to Choice that confirms that the answer's question_id matches, but it sounds like the end user shoul...
AngularJS ngClass conditional
...
Using ng-class inside ng-repeat
<table>
<tbody>
<tr ng-repeat="task in todos"
ng-class="{'warning': task.status == 'Hold' , 'success': task.status == 'Completed',
'active': task.status == 'Started', '...
Combine two ActiveRecord::Relation objects
...ny odd situations, by using Rails' built-in Arel.
User.where(
User.arel_table[:first_name].eq('Tobias').or(
User.arel_table[:last_name].eq('Fünke')
)
)
This merges both ActiveRecord relations by using Arel's or.
Merge, as was suggested here, didn't work for me. It dropped the 2nd set...
How does the socket API accept() function work?
...g on the Server IP maintains a database (meaning I don't care what kind of table/list/tree/array/magic data structure it uses) of active sockets and listens on the Server Port. When it receives a message (via the server's TCP/IP stack), it checks the Client IP and Port against the database. If the...
What is a simple command line program or script to backup SQL server databases?
...tructure to access MSSQL databases. Here's a simple shell script to dump a table to a file:
#!/usr/bin/ksh
#
#.....
(
tsql -S {database} -U {user} -P {password} <<EOF
select * from {table}
go
quit
EOF
) >{output_file.dump}
...
jQuery Selector: Id Ends With?
...ture segments of a title, such as if ID appeard as "masterPage1_Control0_MyTableName_moreStuff" in View Source, I could lock onto the my table of <asp:Table ID="MyTable" ... by using $("id*=MyTable]"). Come to think of it, I like id$ better. Hmmm...
– Lukas
...
JPA: How to have one-to-many relation of the same Entity type
...both). But this resulted in a duplicate row being inserted into my Address table. Is this because I have misconfigured my CascadeType on the User's address field?
– Alex
Aug 25 '13 at 12:17
...
Is ASCII code 7-bit or 8-bit?
...
The original ASCII table is encoded on 7 bits therefore it has 128 characters.
Nowadays most readers/editors use an "extended" ASCII table (from ISO 8859-1), which is encoded on 8 bits and enjoys 256 characters (including Á, Ä, Œ, é, è an...
What is the difference between loose coupling and tight coupling in the object oriented paradigm?
...r", CustomerName);
}
}
class Database
{
public void AddRow(string Table, string Value)
{
}
}
Example of loose coupling:
class CustomerRepository
{
private readonly IDatabase database;
public CustomerRepository(IDatabase database)
{
this.database = database;
...
How to encrypt/decrypt data in php?
...
Foreword
Starting with your table definition:
- UserID
- Fname
- Lname
- Email
- Password
- IV
Here are the changes:
The fields Fname, Lname and Email will be encrypted using a symmetric cipher, provided by OpenSSL,
The IV field will store the init...