tl;dr: As the reference manual states: A block is a piece of Python program text that is executed as a unit. The following are blocks: a module, a function body, and a class definition. Each command typed interactively is a block. This is why, in the case of a function, you have a single code … Read more
Read this very nice article on the subject: Don’t Let Hibernate Steal Your Identity. The conclusion of the article goes like this: Object identity is deceptively hard to implement correctly when objects are persisted to a database. However, the problems stem entirely from allowing objects to exist without an id before they are saved. We … Read more
This is all perfectly normal. Microsoft added sequences in SQL Server 2012, finally, i might add and changed the way identity keys are generated. Have a look here for some explanation. If you want to have the old behaviour, you can: use trace flag 272 – this will cause a log record to be generated … Read more
Changing the IDENTITY property is really a metadata only change. But to update the metadata directly requires starting the instance in single user mode and messing around with some columns in sys.syscolpars and is undocumented/unsupported and not something I would recommend or will give any additional details about. For people coming across this answer on … Read more
Make sure that the Key column’s datatype is int and then setting identity manually, as image shows Or just run this code — ID is the name of the [to be] identity column ALTER TABLE [yourTable] DROP COLUMN ID ALTER TABLE [yourTable] ADD ID INT IDENTITY(1,1) the code will run, if ID is not the … Read more
The @@identity function returns the last identity created in the same session. The scope_identity() function returns the last identity created in the same session and the same scope. The ident_current(name) returns the last identity created for a specific table or view in any session. The identity() function is not used to get an identity, it’s … Read more
is is identity testing, == is equality testing. what happens in your code would be emulated in the interpreter like this: >>> a=”pub” >>> b = ”.join([‘p’, ‘u’, ‘b’]) >>> a == b True >>> a is b False so, no wonder they’re not the same, right? In other words: a is b is the … Read more
In general, the answer to your question is “yes”, but… .equals(…) will only compare what it is written to compare, no more, no less. If a class does not override the equals method, then it defaults to the equals(Object o) method of the closest parent class that has overridden this method. If no parent classes … Read more
Take a look at this: >>> a = 256 >>> b = 256 >>> id(a) 9987148 >>> id(b) 9987148 >>> a = 257 >>> b = 257 >>> id(a) 11662816 >>> id(b) 11662828 Here’s what I found in the Python 2 documentation, “Plain Integer Objects” (It’s the same for Python 3): The current implementation keeps … Read more