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How to stop EditText from gaining focus at Activity startup in Android
I have an Activity in Android, with two elements:
52 Answers
52
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JPA: How to have one-to-many relation of the same Entity type
...
Yes, this is possible. This is a special case of the standard bidirectional @ManyToOne/@OneToMany relationship. It is special because the entity on each end of the relationship is the same. The general case is detailed in Section 2.10.2 of the JPA 2.0 spec.
Here's a worked example. F...
How to use GROUP_CONCAT in a CONCAT in MySQL
...
select id, group_concat(`Name` separator ',') as `ColumnName`
from
(
select
id,
concat(`Name`, ':', group_concat(`Value` separator ',')) as `Name`
from mytbl
group by
id,
`Name`
) tbl
group by id;
You can...
Join/Where with LINQ and Lambda
...ax is much clearer, more natural, and makes it easier to spot errors:
var id = 1;
var query =
from post in database.Posts
join meta in database.Post_Metas on post.ID equals meta.Post_ID
where post.ID == id
select new { Post = post, Meta = meta };
If you're really stuck on using lambda...
SQL order string as number
...the result is 0 */
'123miles' | 123
'$123' | 0 /* the left side of the string does not start with a number */
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How can I override Bootstrap CSS styles?
...oad time for these styles, but it's negligible for the few styles I'm overriding.
12 Answers
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Convert timestamp to date in MySQL query
...SQL
Make the table with an integer timestamp:
mysql> create table foo(id INT, mytimestamp INT(11));
Query OK, 0 rows affected (0.02 sec)
Insert some values
mysql> insert into foo values(1, 1381262848);
Query OK, 1 row affected (0.01 sec)
Take a look
mysql> select * from foo;
+------...
Class does not implement its superclass's required members
...roblem with not implementing or inheriting a required method. There is at least one other reason to make init methods required besides protocol conformance, and that's factory methods.
If I want to write a proper factory method, I need to specify the return type to be Self (Swift's equivalent of Ob...
SqlException from Entity Framework - New transaction is not allowed because there are other threads
...panyFeedDetailList = from a in _dbRiv.AutoNegotiationDetails where a.ClientID == client.ClientID select a;
// ...
}
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MongoDB SELECT COUNT GROUP BY
...er way to do it using aggregate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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