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JPA: unidirectional many-to-one and cascading delete
Say I have a unidirectional @ManyToOne relationship like the following:
7 Answers
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Delete duplicate records in SQL Server?
Consider a column named EmployeeName table Employee . The goal is to delete repeated records, based on the EmployeeName field.
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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...
MySQL COUNT DISTINCT
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Select
Count(Distinct user_id) As countUsers
, Count(site_id) As countVisits
, site_id As site
From cp_visits
Where ts >= DATE_SUB(NOW(), INTERVAL 1 DAY)
Group By site_id
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Objective-C: difference between id and void *
What is the difference between id and void * ?
7 Answers
7
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CodeIgniter activerecord, retrieve last insert id?
Are there any options to get the last insert id of a new record in CodeIgniter?
11 Answers
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Rails params explained?
... Rails has a special syntax for making the params be a hash with hashes inside. For example, if the user's browser requested
http://www.example.com/?vote[item_id]=1&vote[user_id]=2
then params[:vote] would be a hash, params[:vote][:item_id] would be "1" and params[:vote][:user_id] would be "2...
Is there a unique Android device ID?
Do Android devices have a unique ID, and if so, what is a simple way to access it using Java?
52 Answers
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querySelector search immediate children
...ves that is not to their liking), is that they check to see if elem has an ID, and if not, they temporarily add an ID, then create a full selector string.
Basically you'd do:
var sel = '> someselector';
var hadId = true;
if( !elem.id ) {
hadID = false;
elem.id = 'some_unique_value';
}
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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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