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JPA - Returning an auto generated id after persist()
I'm using JPA (EclipseLink) and Spring. Say I have a simple entity with an auto-generated ID:
7 Answers
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What's the $unwind operator in MongoDB?
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First off, welcome to MongoDB!
The thing to remember is that MongoDB employs an "NoSQL" approach to data storage, so perish the thoughts of selects, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which a...
Node.js Mongoose.js string to ObjectId function
Is there a function to turn a string into an objectId in node using mongoose? The schema specifies that something is an ObjectId, but when it is saved from a string, mongo tells me it is still just a string. The _id of the object, for instance, is displayed as objectId("blah") .
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MySQL: How to copy rows, but change a few fields?
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INSERT INTO Table
( Event_ID
, col2
...
)
SELECT "155"
, col2
...
FROM Table WHERE Event_ID = "120"
Here, the col2, ... represent the remaining column...
How to get the device's IMEI/ESN programmatically in android?
...id.telephony.TelephonyManager.getDeviceId().
This will return whatever string uniquely identifies the device (IMEI on GSM, MEID for CDMA).
You'll need the following permission in your AndroidManifest.xml:
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
in order to d...
Count with IF condition in MySQL query
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Use sum() in place of count()
Try below:
SELECT
ccc_news . * ,
SUM(if(ccc_news_comments.id = 'approved', 1, 0)) AS comments
FROM
ccc_news
LEFT JOIN
ccc_news_comments
ON
ccc_news_comments.news_id =...
Pandas get topmost n records within each group
...2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.groupby('id').head(2).reset_index(drop=True) to remove the multindex and flatten the results.
>>&g...
Can I return the 'id' field after a LINQ insert?
When I enter an object into the DB with Linq-to-SQL can I get the id that I just inserted without making another db call? I am assuming this is pretty easy, I just don't know how.
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Sequence contains no matching element
I have an asp.net application in which I am using linq for data manipulation. While running, I get the exception "Sequence contains no matching element".
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Handling colon in element ID with jQuery
We are not able to access the div element with ID "test: abc" in JS code using jQuery.
9 Answers
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