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SQL Add foreign key to existing column
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Error indicates that there is no UserID column in your Employees table. Try adding the column first and then re-run the statement.
ALTER TABLE Employees
ADD CONSTRAINT FK_ActiveDirectories_UserID FOREIGN KEY (UserID)
REFERENCES ActiveDirectories(id);
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How to enter in a Docker container already running with a new TTY
...le to access the container from another shell in order to "poke around" inside it and examine the files. At the moment, if I attach to the container, I am left looking at the Apache daemon and cannot run any commands.
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How to persist a property of type List in JPA?
... String> {
private static final String SPLIT_CHAR = ";";
@Override
public String convertToDatabaseColumn(List<String> stringList) {
return String.join(SPLIT_CHAR, stringList);
}
@Override
public List<String> convertToEntityAttribute(String string) {
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How to determine if a record is just created or updated in after_save
...king to use this for an after_save callback.
A simpler solution is to use id_changed? (since it won't change on update) or even created_at_changed? if timestamp columns are present.
Update: As @mitsy points out, if this check is needed outside of callbacks then use id_previously_changed?. See docs...
When to use .First and when to use .FirstOrDefault with LINQ?
... @driis - I'd imagine we can use the mantra of the exceptional exception guideline when choosing between First and FirstOrDefault. Thanks for the clear answer.
– Metro Smurf
Jun 21 '09 at 21:21
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How do you do a limit query in JPQL or HQL?
...tMaxResults().
So if it worked in Hibernate 2, it seems that was by coincidence, rather than by design. I think this was because the Hibernate 2 HQL parser would replace the bits of the query that it recognised as HQL, and leave the rest as it was, so you could sneak in some native SQL. Hibernate ...
How to declare a variable in a PostgreSQL query
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This is ideal for when I have a migration script where I want to import some relational data. Obviously I won't know the sequence id the relational data is given.
– Relequestual
Feb 13 '15 at 9:...
Check if checkbox is checked with jQuery
How can I check if a checkbox in a checkbox array is checked using the id of the checkbox array?
23 Answers
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Jenkins Host key verification failed
...tal: The remote end hung up unexpectedly
– A. M. Mérida
Mar 4 '13 at 8:40
6
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mongodb count num of distinct values per field/key
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},
{ $unwind: "$keywords" },
{
$group: {
_id: {$toLower: '$keywords'},
count: { $sum: 1 }
}
},
{
$match: {
count: { $gte: 2 }
}
},
{ $sort : { count : -1} },
{ $limit : 100 }
]);
that give result s...