This is more of a big data question(GFS related). I'm not getting how checkpointing help? Can you share 1 example(which could be DBMS example).
Say these are the operations on the database....
Hello, I was checking this How to show date time with am/pm using C# in ASP.NET? but I would like to know simple C# code to get only time from datetime in C#. So for example, If I have ' 09/04/2022 03:52 PM', i need only '03:53 PM'....
The answer is this-: Because we can't declare a field of different data types within a same index in different document types.
Say there's an index called "college".
Then there are document types called "student" "teacher" "administration" "staff".
What problem would occur if we allow this?
Books and documentations are saying that if a field called "date_of_join" is given a "text" data type in "student", then we can't give "date_of_join" as "date" data type in "staff".
It says that it's due to the way Lucene is.
This is because of the way Lucene maintains the field types in an index. As Lucene manages fields on an index level, there is no flexibility to declare two fields of different data types in the same index
But this is not clear without an example(of how lucene is storing index). Can you guys clarify this?
I know that lucene stores inverted indexes though. But still I'm not clear....
I find it simple. Have a CDN edge server near the user, cache the request and when next time he asks for it, give it. But I am pretty sure what I am thinking, although correct, isn't complete and there is something missing.
My book has just included some small benefits of CDN, that's all. But that too isn't given in detail with illustrations(although it is not necessary i feel). Exam questions of mine has asked like how CDN reduces delay in received requested object for 8 marks(3hrs exam, 80 full marks).
The answer to this is literally 1 line ie the definition of CDN. and maybe 2 figures showing how it works with and without CDN. another question asked in the exam is-: how proxy CDN works, explain with example.
I am not sure how the updating of content happens.
Does only 1 proxy server gets updated or do all proxy servers get updated when 1 CDN brings a fresh copy of the web page from the origin server? It is confusing; believe me, the tutorials for this thing are advertisements for various CDNs....
Figure i am talking about-:
Confusions, "ie" means my interpretation that i am not sure if is correct or not)-:
1) user clicks invoking an event handler.
2) handler's code creates xmlhttprequest object
3) xhr requests file from server
4) server sends the file.
5) NOW I AM CONFUSED.
the terminologies are confusing me.
handler fxn then processes the data and displays it....
When I am trying to execute this query in MySQL Workbench '
DELETE FROM Job;', I am getting below error
Error Code: 1175. You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. To disable safe mode, toggle the option in Preferences -> SQL Editor and reconnect.
So, how can I resolve this error, why I cannot Execute the simple delete query?...