Today we continue reviewing U-SQL.It unifies the benefits of SQL with the expressive power of your own code. This is said to work very well with all kind of data stores – file, object and relational. U-SQL works on the Azure ecosystem which involves the Azure data lake storage as the foundation and the analytics layer over it. The benefit of the Azure storage is that it spans several kinds of data formats and stores.
U-SQL is a data processing language.Like SQL, it has declarative language and procedural control flow. The difference between imperative and declarative language is that Imperative means we tell the system how to get the data. Declarative means we tell the system what we want and the system finds a way to get it. The optimizer decides how to do it best. The difference between procedural and functional is that procedural means it operates by changing persistent state with each expression Functional means it transforms input into output with no persistent state. Single objects require control flow. Single objects requires control flows and may require parallelism to be explained. With the data model, we can use higher level data abstractions. There is scale up versus scale out. Programming languages required data in a store and does not make it part of the language model. Data and logic go together. It is imperative and procedural. Data processing languages on the other hand make data part of the language model. It can be both declarative and functional. The data can evolve independently of the application and the optimizer decides the parallelism and
U-SQL like T-SQL provides important benefits with query language. First and foremost, there is consistency and familiarity with its usage. The learning curve and the onboarding from T-SQL to U-SQL is not very steep. Moreover, there is a lot of thought behind the syntax. It is context independent and defined in data processing language. It is also composable. It is important for the query language to be precise and accurate while at the same time be convenient for the user. There is writeability versus readability separation of concerns. All of these are important considerations in U-SQL. In addition to the syntax, the semantics also matter. U-SQL tries to avoid surprises and complexities. Moreoever as a language it is composable for the user and optimizable for the system.
Courtesy U-SQL slide shares
My take on query improvements : https://1drv.ms/w/s!Ashlm-Nw-wnWsFqBcG-mBhjPLbC8
#codingexercise
Given n friends, each one can remain single or can be paired up with some other friend. Each friend can be paired only once so ordering is irrelevant. Find the total number of ways in which the friends can be paired.
Let us define a recursive method to do this which takes a parameter n.
When n is less than two, the number of friends returned is n
If the number of friends is greater than two, then they can be formed excluding one which is the equivalent of calling the recursive method n-1 times. In addition, they can also be formed by pairing all the others excluding this one which is n-1 with the number of friends formed by removing two members
F(n) = F(n-1) + (n-1) F(n-2)
U-SQL is a data processing language.Like SQL, it has declarative language and procedural control flow. The difference between imperative and declarative language is that Imperative means we tell the system how to get the data. Declarative means we tell the system what we want and the system finds a way to get it. The optimizer decides how to do it best. The difference between procedural and functional is that procedural means it operates by changing persistent state with each expression Functional means it transforms input into output with no persistent state. Single objects require control flow. Single objects requires control flows and may require parallelism to be explained. With the data model, we can use higher level data abstractions. There is scale up versus scale out. Programming languages required data in a store and does not make it part of the language model. Data and logic go together. It is imperative and procedural. Data processing languages on the other hand make data part of the language model. It can be both declarative and functional. The data can evolve independently of the application and the optimizer decides the parallelism and
U-SQL like T-SQL provides important benefits with query language. First and foremost, there is consistency and familiarity with its usage. The learning curve and the onboarding from T-SQL to U-SQL is not very steep. Moreover, there is a lot of thought behind the syntax. It is context independent and defined in data processing language. It is also composable. It is important for the query language to be precise and accurate while at the same time be convenient for the user. There is writeability versus readability separation of concerns. All of these are important considerations in U-SQL. In addition to the syntax, the semantics also matter. U-SQL tries to avoid surprises and complexities. Moreoever as a language it is composable for the user and optimizable for the system.
Courtesy U-SQL slide shares
My take on query improvements : https://1drv.ms/w/s!Ashlm-Nw-wnWsFqBcG-mBhjPLbC8
#codingexercise
Given n friends, each one can remain single or can be paired up with some other friend. Each friend can be paired only once so ordering is irrelevant. Find the total number of ways in which the friends can be paired.
Let us define a recursive method to do this which takes a parameter n.
When n is less than two, the number of friends returned is n
If the number of friends is greater than two, then they can be formed excluding one which is the equivalent of calling the recursive method n-1 times. In addition, they can also be formed by pairing all the others excluding this one which is n-1 with the number of friends formed by removing two members
F(n) = F(n-1) + (n-1) F(n-2)
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