Month: May 2020

When working with code generated solutions we often need to convert datasets from SQL Server (T-SQL) data types to Azure Data Lake Analytics (U-SQL) data types. As you probably know U-SQL has a hybrid syntax of T-SQL and C# which Read More …

There are 5 kinds of User-Defined entities in U-SQL User-Defined Functions (UDFs)User-Defined Types (UDTs)User-Defined Aggregators (UDAggs)User-defined Operators (UDOs)User-Defined Appliers All of them are defined by .NET code. C# is not required. Any .NET language will work. User-Defined Functions User defined functions are normal static methods on a .NET Class. Read More …

Set operations are a way of merging rowsets together based on set theoretic operations such as union (UNION). intersection (INTERSECT), complement (EXCEPT). Sample data Let’s define two RowSets: @a and @b. Notice that both RowSets have duplicate rows. UNION UNION combines two rowsets. UNION Read More …

Window functions were introduced to the ISO/ANSI SQL Standard in 2003. U-SQL adopts a subset of window functions as defined by the ANSI SQL Standard. Window functions are used to do computation within sets of rows called windows. Windows are defined Read More …

The U-SQL Catalog is the way U-SQL organizes data and code for re-use and sharing. Catalog organization Every ADLA account has a single U-SQL catalog. The catalog cannot be deleted.Each U-SQL catalog contains one or more U-SQL databases.Every catalog has Read More …

Reading and Writing Files: Built-in Extractors U-SQL has three built-in extractors that handle text Extractors.Csv() reads comma-separated value (CSV)Extractors.Tsv() reads tab-separated value (TSV)Extractors.Text() reads delimited text files. Extractors.Csv and Extractors.Tsv are the same as Extractors.Text but they default to a specific delimiter appropriate for the format they support. Read More …

Overview Clauses such as SELECT, WHERE, and HAVING (among others) allow you to enter U-SQL expressions. An expression in a programming language is a combination of explicit values, constants, variables, operators, and functions that are interpreted according to the particular rules of precedence and Read More …

The DECLARE statement allows us to define parameters to store values for things that aren’t RowSets. We’ll start with this snippet DECLARE can assign constant values to a name. In this case we can assign the input file to a parameter. Parameter values Read More …

In this chapter you’ll focus on the fundamental ways in which rowsets can be created and modified. Creating a RowSet from another RowSet Effectively this script just copies the data without transforming it. However, if you look at the output Read More …

In this blog you will master the mechanics of running U-SQL on your own box with Visual Studio. You will also get familiar with basic U-SQL concepts. If you come from a SQL background, you’ll notice that U-SQL queries look Read More …