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How should equals and hashcode be implemented when using JPA and Hibernate
...ces your entity in bucket #1. b) your entity (within set) is persisted, it now does have an id and thus you're using hashCode() based on that id. It's different from above and would have placed your entity in the bucket #2. Now, assuming you hold a reference to this entity elsewhere, try calling Set...
Filter dataframe rows if value in column is in a set list of values [duplicate]
... string
... '600141' ...
... '600329' ...
... ... ...
Suppose now we have a list of strings which we want the values in 'STK_ID' to end with, e.g.
endstrings = ['01$', '02$', '05$']
We can join these strings with the regex 'or' character | and pass the string to str.contains to filte...
What is a plain English explanation of “Big O” notation?
... then initials or first name, possibly address and then telephone numbers.
Now if you were instructing a computer to look up the phone number for "John Smith" in a telephone book that contains 1,000,000 names, what would you do? Ignoring the fact that you could guess how far in the S's started (let...
Database sharding vs partitioning
... multiple instances or servers, using some kind of logic or identifier to know which instance or server to look for the data. An identifier of this kind is often called a "Shard Key".
A common, key-less logic is to use the alphabet to divide the data. A-D is instance 1, E-G is instance 2 etc. Custo...
How can I view array structure in JavaScript with alert()?
...
EDIT: Firefox and Google Chrome now have a built-in JSON object, so you can just say alert(JSON.stringify(myArray)) without needing to use a jQuery plugin. This is not part of the Javascript language spec, so you shouldn't rely on the JSON object being pre...
Extract a dplyr tbl column as a vector
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@mzuba I would use the pull command now. My solution was written prior to dplyr version 0.6.
– rrs
Jun 20 '18 at 13:12
1
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Bind TextBox on Enter-key press
...rigger=PropertyChanged" to "UpdateSourceTrigger=Explicit" fixed the issue. Now it all works as desired.
– ihake
Jun 18 '14 at 16:51
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How to grant remote access to MySQL for a whole subnet?
... apply to: user_name@'192.168.1.my-hacked-rnds.killing.mysql.com'???? i'll now walk on, since this being MySQL I sense I don't want to know the answer.
– Florian Heigl
Apr 24 '15 at 19:24
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How to write inline if statement for print?
...ilarly when you write
x = a if b else 0
it means
x = (a if b else 0)
Now what would it print/assign if there was no else clause? The print/assignment is still there.
And note, that if you don't want it to be there, you can always write the regular if statement on a single line, though it's le...
How can I retrieve Id of inserted entity using Entity framework? [closed]
...ges();//adds customer.Id to customer and the correct CustomerId to order
Now when I save the changes the id that is generated for customer is also added to order. I've no need for the additional steps
I'm aware this doesn't answer the original question but thought it might help developers who are...