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generate model using user:references vs user_id:integer
..., you can see that this is the case:
:001 > Micropost
=> Micropost(id: integer, user_id: integer, created_at: datetime, updated_at: datetime)
The second command adds a belongs_to :user relationship in your Micropost model whereas the first does not. When this relationship is specified, Ac...
When tracing out variables in the console, How to create a new line?
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You should include it inside quotes '\n', See below,
console.log('roleName = '+roleName+ '\n' +
'role_ID = '+role_ID+ '\n' +
'modal_ID = '+modal_ID+ '\n' +
'related = '+related);
...
selecting unique values from a column
...o if you want the whole record, the DISTINCT is worthless (unless it is an id field, and you can do a second query where id IN that list). Good news, though, if you have multiple duplicate results as a result of a JOIN you can do a GROUP BY and get the full results filtered.
– ...
For each row return the column name of the largest value
...what department they are in most often. It is trivial to tabulate employee ID against department name, but it is trickier to return the department name, rather than the number of roster counts, from the frequency table. A simple example below (column names = departments, row names = employee ids).
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How to delete a certain row from mysql table with same column values?
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Add a limit to the delete query
delete from orders
where id_users = 1 and id_product = 2
limit 1
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Reset auto increment counter in postgres
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If you created the table product with an id column, then the sequence is not simply called product, but rather product_id_seq (that is, ${table}_${column}_seq).
This is the ALTER SEQUENCE command you need:
ALTER SEQUENCE product_id_seq RESTART WITH 1453
You can ...
Surrogate vs. natural/business keys [closed]
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If you have multiple "candidate" keys (fields or same-size collections of fields that are NOT NULL UNIQUE) then you are likely in violation of Boyce-Codd Normal Form. BCNF is beyond 3NF, so not many people worry about it. There are situations, howev...
Making TextView scrollable on Android
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You don't need to use a ScrollView actually.
Just set the
android:scrollbars = "vertical"
properties of your TextView in your layout's xml file.
Then use:
yourTextView.setMovementMethod(new ScrollingMovementMethod());
in your code.
Bingo, it scrolls!
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How to find largest objects in a SQL Server database?
...ceMB
FROM
sys.tables t
INNER JOIN
sys.indexes i ON t.object_id = i.object_id
INNER JOIN
sys.partitions p ON i.object_id = p.object_id AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
WHERE
t.name NOT LIKE 'dt%' AND
i.o...
Deserialize JSON with C#
...d> data {get; set;}
}
public class FacebookFriend
{
public string id {get; set;}
public string name {get; set;}
}
Then you should be able to do:
Friends facebookFriends = new JavaScriptSerializer().Deserialize<Friends>(result);
The names of my classes are just an example. You...