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Sequelize Unknown column '*.createdAt' in 'field list'
..., which creates the following query:
SELECT `users`.*, `userDetails`.`userId` AS `userDetails.userId`,`userDetails`.`firstName` AS `userDetails.firstName`,`userDetails`.`lastName` AS `userDetails.lastName`, `userDetails`.`birthday` AS `userDetails.birthday`, `userDetails`.`id` AS `userDetails.id`, ...
CHECK constraint in MySQL is not working
... answered Jan 22 '10 at 7:11
David KerinsDavid Kerins
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...
Numbering rows within groups in a data frame
...l, df$cat, FUN = seq_along)
or:
library(plyr)
ddply(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memory efficient, as it assigns by reference within DT):
library(data.table)
DT <- data.table(df)
DT[, id...
NULL vs nil in Objective-C
...
nil should only be used in place of an id, what we Java and C++ programmers would think of as a pointer to an object. Use NULL for non-object pointers.
Look at the declaration of that method:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object...
How do you specify that a class property is an integer?
...rimenting with TypeScript, and in the process of creating a class with an "ID" field that should be an integer, I have gotten a little confused.
...
jQuery UI Dialog with ASP.NET button postback
...true,
show: 'Transfer',
hide: 'Transfer',
width: 320,
autoOpen: false,
minHeight: 10,
minwidth: 10
});
dlg.parent().appendTo(...
What are best practices for REST nested resources?
As far as I can tell each individual resource should have only one canonical path. So in the following example what would good URL patterns be?
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Tying in to Django Admin's Model History
...min.models import LogEntry, ADDITION
LogEntry.objects.log_action(
user_id = request.user.pk,
content_type_id = ContentType.objects.get_for_model(object).pk,
object_id = object.pk,
object_repr = force_unicode(object),
action_flag = ADDITION
)
where object...
How to choose the id generation strategy when using JPA and Hibernate
I was going through Id generation section of the Hibernate reference guide and "java persistence with Hibernate"
4 Answers
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@UniqueConstraint and @Column(unique = true) in hibernate annotation
...
As said before, @Column(unique = true) is a shortcut to UniqueConstraint when it is only a single field.
From the example you gave, there is a huge difference between both.
@Column(unique = true)
@ManyToOne(optional = false, fet...