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Rails find_or_create_by more than one attribute?
...
Multiple attributes can be connected with an and:
GroupMember.find_or_create_by_member_id_and_group_id(4, 7)
(use find_or_initialize_by if you don't want to save the record right away)
Edit: The above method is deprecated in Rails 4. The new way to do it will be:
GroupMe...
Pandas dataframe get first row of each group
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>>> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 f...
How can I make space between two buttons in same div?
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Put them inside btn-toolbar or some other container, not btn-group. btn-group joins them together. More info on Bootstrap documentation.
Edit: The original question was for Bootstrap 2.x, but the same is still valid for Bootstrap 3 and Bootstrap 4.
In Bootstrap 4 you will need to add...
LEFT JOIN only first row
...fa ON fa.feed_id = f.id
LEFT JOIN artists a ON fa.artist_id = a.artist_id
GROUP BY f.id
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Bootstrap 3 panel header with buttons wrong position
...="padding-top: 7.5px;">Panel header</h4>
<div class="btn-group pull-right">
<a href="#" class="btn btn-default btn-sm">## Lock</a>
<a href="#" class="btn btn-default btn-sm">## Delete</a>
<a href="#" class="btn btn-default btn-s...
Possible reasons for timeout when trying to access EC2 instance
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Did you set an appropriate security group for the instance? I.e. one that allows access from your network to port 22 on the instance. (By default all traffic is disallowed.)
Update: Ok, not a security group issue. But does the problem persist if you launch up ...
Switching the order of block elements with CSS [duplicate]
... box-orient: vertical;
}
#blockA {
-webkit-box-ordinal-group: 2;
-moz-box-ordinal-group: 2;
box-ordinal-group: 2;
}
#blockB {
-webkit-box-ordinal-group: 3;
-moz-box-ordinal-group: 3;
box-ordinal-group: 3;
}
<div ...
Remove duplicated rows using dplyr
... y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data frame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won...
sed: print only matching group
...regex. This causes the entire line to be replaced with the contents of the group
echo "foo bar <foo> bla 1 2 3.4" |
sed -n 's/.*\([0-9][0-9]*[\ \t][0-9.]*[ \t]*$\)/\1/p'
2 3.4
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How do you find the row count for all your tables in Postgres
...ults to your favorite text editor (it will look like this:
public | auth_group | table | axrsosvelhutvw
public | auth_group_permissions | table | axrsosvelhutvw
public | auth_permission | table | axrsosvelhutvw
public | auth_user |...