Misc Flashcards
What is the difference between a data lake and a data warehouse in Azure?
A data lake holds data of all structure types, including raw and unprocessed data.
A data warehouse stores data that has been treated and transformed with a specific purpose in mind, which can then be used to source analytic or operational reporting.
What is Delta Lake?
An open approach to bringing data management and governance to data lakes
Cluster Types
All-Purpose - notebooks
Job - automated jobs
UML
Unified Modeling Language
Boxing
When a struct value is assigned to a variable that stores references, like the first line above, the
data is pushed out to another location on the heap, in its own little container—a box. A
reference to the box is then stored in the thing variable.
object thing = 3;
Unboxing
After ensuring that the type is correct, the box’s
contents are extracted—an unboxing conversion—and copied into the number variable.
int number = (int)thing;
Records
public record Point(float X, float Y); // That’s all.
The typical situation where a record makes sense is when your type
is little more than a set of properties—a data-focused entity.
Difference between struct and class
struct is value type and class is reference type
generic type contrainst
Where T : objectType
restricts a generic to specified type
stringbuilder
saves memory by hanging on to fragments of strings and not assembling them into final string until it is done
difference between out and ref
ref - must be initialized first
out - need not be initialized first but initialized in the method
difference between throw and throw e
throw - A bare throw; statement will rethrow the caught exception without modifying its original
stack trace
throw e -
difference between throw and throw e
throw - A bare throw; statement will rethrow the caught exception without modifying its original
stack trace
throw e - That
means when you throw an exception, as shown above, the stack trace will change to its new
location in this catch block, losing useful information.
delegate
a variable that stores methods, allowing them to be passed around like an object
closure
A method plus any captured variables from its
environment is called a closure
