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Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
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You are missing a field annotated with @Id. Each @Entity needs an @Id - this is the primary key in the database.
If you don't want your entity to be persisted in a separate table, but rather be a part of other entities, you can use @Embeddable instead of @Entity....
Get the latest record from mongodb collection
...oDB are B-Trees. Searching a B-Tree is a O(logN) operation, so even find({_id:...}) will not provide constant time, O(1) responses.
That stated, you can also sort by the _id if you are using ObjectId for you IDs. See here for details. Of course, even that is only good to the last second.
You may t...
MySQL Update Inner Join tables query
I have no idea what the problem is. Using MySQL 5.0 I get a compile error when attempting to run the following MySQL update query:
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JOIN queries vs multiple queries
...ins, multiple queries is much better... look at the following benchmark I did:
Single query with 5 Joins
query: 8.074508 seconds
result size: 2268000
5 queries in a row
combined query time: 0.00262 seconds
result size: 165 (6 + 50 + 7 + 12 + 90)
.
Note that we get the same results in both ...
Accessing MP3 metadata with Python [closed]
...other day with a lot of success. I found that it could add artwork to the ID3 tag which the other modules I looked at couldn't. You'll have to install using pip or download the tar and execute python setup.py install from the source folder.
Relevant examples from the website are below.
Reading...
REST API Best practices: Where to put parameters? [closed]
...nted best practices, I have not found them yet. However, here are a few guidelines I use when determining where to put parameters in an url:
Optional parameters tend to be easier to put in the query string.
If you want to return a 404 error when the parameter value does not correspond to an exist...
Wildcards in jQuery selectors
I'm trying to use a wildcard to get the id of all the elements whose id begin with "jander". I tried $('#jander*') , $('#jander%') but it doesn't work..
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Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes
...p:ajax process> <f:ajax execute>
The process attribute is server side and can only affect UIComponents implementing EditableValueHolder (input fields) or ActionSource (command fields). The process attribute tells JSF, using a space-separated list of client IDs, which components exactly must...
Rails auto-assigning id that already exists
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Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
SELECT setval('company_id_seq', (SELECT max(...
List the queries running on SQL Server
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This will show you the longest running SPIDs on a SQL 2000 or SQL 2005 server:
select
P.spid
, right(convert(varchar,
dateadd(ms, datediff(ms, P.last_batch, getdate()), '1900-01-01'),
121), 12) as 'batch_duration'
, P.program_name
...