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Is a Java string really immutable?
We all know that String is immutable in Java, but check the following code:
15 Answers
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How to get image height and width using java?
... byte: H is first four bits and V is second four bits
o Quantization table number-- one byte
The H and V sampling factors dictate the final size of the component they are associated with. For instance, the color space defaults to YCbCr and the H and V sampling factors for each component, Y, C...
grant remote access of MySQL database from any IP address
...SERNAME'@'1.2.3.4';
Its better to check information_schema.user_privileges table after running REVOKE command.
If you see USAGE privilege after running REVOKE command, its fine. It is as good as no privilege at all. I am not sure if it can be revoked.
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Get an array of list element contents in jQuery
...y to the list taking values from two different columns from each rows of a table. Isn't there easier way to do that? Thanks in advance.
– ln2khanal
Dec 6 '13 at 15:54
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Hashset vs Treeset
...some sense intermediate between HashSet and TreeSet. Implemented as a hash table with a linked list running through it, however,it provides insertion-ordered iteration which is not same as sorted traversal guaranteed by TreeSet.
So a choice of usage depends entirely on your needs but I feel that e...
How to return multiple lines JSX in another return statement in React?
...ed to return multiple <tr>s. I wrapped them in a <tbody> – a table is allowed to have multiple bodies.
EDIT: As of React 16.0, returning an array is apparently allowed again, as long as each element has a key: https://facebook.github.io/react/blog/2017/09/26/react-v16.0.html#new-rende...
How to run Django's test database only in memory?
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You can do double tweaking:
use transactional tables: initial fixtures state will be set using database rollback after every TestCase.
put your database data dir on ramdisk: you will gain much as far as database creation is concerned and also running test will be faster....
What is the difference between pluck and collect in Rails?
...asting memory and time. Because it will retrieve all the columns from user table in the database, allocates the memory for each attributes (including the attributes which you will never use)
NOTE: pluck does not return ActiveRecord_Relation of the user
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django models selecting single field
I have a table/models called Employees and I would like to get all rows of a single field as a queryset.
5 Answers
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When to use PNG or JPG in iPhone development?
...ded to use PNG's for any images that appear as part of the interface (in a table view, labels, etc).
As for displaying a full screen image such as a photograph you may still reap benefits with PNG's since they are non-lossy and the visual quality should be better than a JPG not to mention resource...