From d37ec2b7b759831458dbb512fdb508ccb2b30d94 Mon Sep 17 00:00:00 2001 From: Jovan Popovic Date: Wed, 20 Dec 2017 14:42:38 +0100 Subject: [PATCH] Added README to TCC sample --- .../sql-clr/TransitiveClosure/README.md | 79 +++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 samples/features/sql-clr/TransitiveClosure/README.md diff --git a/samples/features/sql-clr/TransitiveClosure/README.md b/samples/features/sql-clr/TransitiveClosure/README.md new file mode 100644 index 00000000..bb8bff87 --- /dev/null +++ b/samples/features/sql-clr/TransitiveClosure/README.md @@ -0,0 +1,79 @@ +# Implementing Transitive Closure Clustering in SQL Server using CLR UDF +SQL Database don't have built-in support for transitive closure clustering, so the only workaround is to implement this algorithm in .Net framework and expose it as T-SQL function. +This code sample demonstrates how to create CLR User-Defined aggregate that implements clustering. + +### Contents + +[About this sample](#about-this-sample)
+[Build the CLR/RegEx functions](#build-functions)
+[Add RegEx functions to your SQL database](#add-functions)
+[Test the functions](#test)
+[Disclaimers](#disclaimers)
+ + + +## About this sample +1. **Applies to:** SQL Server 2016+ Enterprise / Developer / Evaluation Edition +2. **Key features:** + - CLR, JSON +3. **Programming Language:** .NET C# +4. **Author:** Davide Mauri, Jovan Popovic [jovanpop-msft] + + + +## Build the CLR/RegEx functions + +1. Download the source code and open the solution using Visual Studio. +2. Change the password in .pfk file and rebuild the solution in **Release** mode. +3. Open and save TransitiveClosure.tt to generate output T-SQL file that will contain script that inserts .dll file with the Transitive closure clustering aggregate. + + +## Add Clustering aggregate to your SQL database + +File TransitiveClosure.sql contains the code that will import aggregate into SQL Database. + +If you have not added CLR assemblies in your database, you should use the following script to enable CLR: +``` +sp_configure @configname=clr_enabled, @configvalue=1 +GO +RECONFIGURE +GO +``` + +Once you enable CLR, you can use the T-SQL script to add the clustering aggregate. The script depends on the location where you have built the project, and might look like: +``` +CREATE ASSEMBLY TransitiveClosure FROM 'D:\GitHub\sql-server-samples\samples\features\sql-clr\TransitiveClosure\bin\Release\TransitiveClosureAggregatorLibrary.dll' WITH PERMISSION_SET = SAFE; +GO + +CREATE SCHEMA TC; +GO + +CREATE AGGREGATE TC.CLUSTERING(@id1 INT, @id2 INT) +RETURNS NVARCHAR(MAX) +EXTERNAL NAME TransitiveClosure.[TransitiveClosure.Aggregate]; +``` + +This code will import assembly in SQL Database and add three functions that provide clustering functionalities. + + + +## Test the function + +Once you create the assembly and expose the functions, you can use it to cluster some relational data in T-SQL code: + +``` +declare @edges table(n1 int, n2 int); + +insert into @edges +values (1,2),(2,3),(3,4),(4,5),(2,21),(2,22), +              (7,8),(8,9),(9,10); + +select TC.CLUSTERING(n1,n2) +from @edges; +``` + + + +## Disclaimers +The code included in this sample is not intended to be a set of best practices on how to build scalable enterprise grade applications. This is beyond the scope of this sample. +