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How do I handle too long index names in a Ruby on Rails ActiveRecord migration?
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Provide the :name option to add_index, e.g.:
add_index :studies,
["user_id", "university_id", "subject_name_id", "subject_type_id"],
:unique => true,
:name => 'my_index'
If using the :index option on references in...
Cannot delete or update a parent row: a foreign key constraint fails
...dvertisers`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER T...
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 first
1 ...
Adding parameter to ng-click function inside ng-repeat doesn't seem to work
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Instead of
<button ng-click="removeTask({{task.id}})">remove</button>
do this:
<button ng-click="removeTask(task.id)">remove</button>
Please see this fiddle:
http://jsfiddle.net/JSWorld/Hp4W7/34/
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Cast Int to enum in Java
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Try MyEnum.values()[x] where x must be 0 or 1, i.e. a valid ordinal for that enum.
Note that in Java enums actually are classes (and enum values thus are objects) and thus you can't cast an int or even Integer to an enum.
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How to set caret(cursor) position in contenteditable element (div)?
...the following:
function setCaret() {
var el = document.getElementById("editable")
var range = document.createRange()
var sel = window.getSelection()
range.setStart(el.childNodes[2], 5)
range.collapse(true)
sel.removeAllRanges()
sel.addRange(range)
}
<div...
Alternate output format for psql
...on Ubuntu. I have a table with columns c1 through cN . The columns are wide enough that selecting all columns causes a row of query results to wrap multiple times. Consequently, the output is hard to read.
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Get real path from URI, Android KitKat new storage access framework [duplicate]
Before the new gallery access in Android 4.4 (KitKat) I got my real path on the SD card with this method:
9 Answers
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On delete cascade with doctrine2
...e to the foreign key column in the database:
@ORM\JoinColumn(name="father_id", referencedColumnName="id", onDelete="CASCADE")
I also want to point out that the way you have your cascade={"remove"} right now, if you delete a Child object, this cascade will remove the Parent object. Clearly not wha...
How to get form field's id in Django?
Is there any way to get the id of a field in a template?
4 Answers
4
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