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Questions tagged [identity]

An inherent property of an entity that distinguishes that entity from all others. Frequently used to refer to user identity and authentication.

Identity typically refers to user identity in authentication scenarios.

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Why does comparing strings using either '==' or 'is' sometimes produce a different result?

I've got a Python program where two variables are set to the value 'public'. In a conditional expression I have the comparison var1 is var2 which fails, but if I change it to var1 == var2 it returns True. Now if I open my Python interpreter and do…
jottos
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What is the difference between == and equals() in Java?

I wanted to clarify if I understand this correctly: == is a reference comparison, i.e. both objects point to the same memory location .equals() evaluates to the comparison of values in the objects
brainydexter
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"is" operator behaves unexpectedly with integers

Why does the following behave unexpectedly in Python? >>> a = 256 >>> b = 256 >>> a is b True # This is an expected result >>> a = 257 >>> b = 257 >>> a is b False # What happened here? Why is this False? >>> 257 is 257 True …
Greg Hewgill
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Auto increment primary key in SQL Server Management Studio 2012

How do I auto increment the primary key in a SQL Server database table, I've had a look through the forum but can't see how. I've looked the the properties but can't see an option, I have seen an answer where you go to the Identity specification…
Ledgemonkey
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The JPA hashCode() / equals() dilemma

There have been some discussions here about JPA entities and which hashCode()/equals() implementation should be used for JPA entity classes. Most (if not all) of them depend on Hibernate, but I'd like to discuss them JPA-implementation-neutrally (I…
MRalwasser
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How to get the unique ID of an object which overrides hashCode()?

When a class in Java doesn't override hashCode(), printing an instance of this class gives a nice unique number. The Javadoc of Object says about hashCode(): As much as is reasonably practical, the hashCode method defined by class Object does…
ivan_ivanovich_ivanoff
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ASP.NET MVC 5 - Identity. How to get current ApplicationUser

I have an Article entity in my project which has the ApplicationUser property named Author. How can I get the full object of currently logged ApplicationUser? While creating a new article, I have to set the Author property in Article to the current…
Ellbar
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What is the difference between Scope_Identity(), Identity(), @@Identity, and Ident_Current()?

I know Scope_Identity(), Identity(), @@Identity, and Ident_Current() all get the value of the identity column, but I would love to know the difference. Part of the controversy I'm having is what do they mean by scope as applied to these functions…
Tebo
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How to change identity column values programmatically?

I have a MS SQL 2005 database with a table Test with column ID. ID is an identity column. I have rows in this table and all of them have their corresponding ID auto incremented value. Now I would like to change every ID in this table like this: ID…
Tomasz Smykowski
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SQL Server 2012 column identity increment jumping from 6 to 1000+ on 7th entry

I have a strange scenario in which the auto identity int column in my SQL Server 2012 database is not incrementing properly. Say I have a table which uses an int auto identity as a primary key it is sporadically skipping increments, for…
Andy Clark
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Generating human-readable/usable, short but unique IDs

Need to handle > 1000 but < 10000 new records per day Cannot use GUID/UUIDs, auto increment numbers etc. Ideally should be 5 or 6 chars long, can be alpha of course Would like to reuse existing, well-known algos, if available Anything out there ?
Kumar
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How to insert into a table with just one IDENTITY column?

(Came up with this question in the course of trying to answer this other one) Consider the following MS-SQL table, called GroupTable: GroupID ------- 1 2 3 where GroupID is the primary key and is an Identity column. How do you insert a new…
codeulike
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What is the purpose of the ConcurrencyStamp column in the AspNetUsers table in the new ASP.NET MVC 6 identity?

What is the purpose of the ConcurrencyStamp column in the AspNetUsers table in the new ASP.NET MVC 6 identity? This is the database schema of the AspNetUsers table: It is also there in the AspNetRoles table: As I remember it wasn't there in the…
Nikolay Kostov
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Programmatically get a Storyboard ID?

Trying to see if a UIViewController or UIView can identify its Storyboard ID. So was hoping for: UIViewController *aViewController; NSString *storyboardID = aViewController.storyboard.id; //not an actual property or: NSString *storyboardID =…
Jalakoo
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How to generate unique id in Dart

I write websocket chat. How to generate unique id for user? now i use this code: id = new DateTime.now().millisecondsSinceEpoch; is there any more neat solution?
Sergey Karasev
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