It is pretty much very common to have a sample database for any database product. Different companies keep on improving their product and keep on coming up with innovation in their product. To demonstrate the capability of their new enhancements they need the sample database. Microsoft have various sample database available for free download for their SQL Server Product. I have collected them here in a single blog post.

Download an AdventureWorks Database
The AdventureWorks OLTP database supports standard online transaction processing scenarios for a fictitious bicycle manufacturer (Adventure Works Cycles). Scenarios include Manufacturing, Sales, Purchasing, Product Management, Contact Management, and Human Resources.

Coconut Dal
Coconut Dal is a lightweight data access layer, for use in projects where the Entity Framework cannot be used or Microsoft’s Enterprise Library Data Block is unsuitable. Anyone who is handwriting ADO.NET should use a library instead and Coconut Dal might be the answer. 

DataBooster – Extension to ADO.NET Data Provider
The dbParallel DataBooster library is a high-performance extension to ADO.NET Data Provider, includes two aspects: 1) A slimmed down API encapsulation which simplified the most common data access operations (DbConnection -> DbCommand -> DbParameter -> DbDataReader) into a single class DbAccess, to help application with a clean DAL, avoid over-packing and redundant-copy of data transfer. 2) A booster for writing mass data onto database. Base on a rational utilization of database concurrency and a effective utilization of network bandwidth.

Tabular AMO 2012
The sample is made of two project parts. The first part is a library of functions to manage tabular models -AMO2Tabular V2-. The second part is a sample to build a tabular model -AdventureWorks Tabular AMO 2012- using the AMO2Tabular library; the created model is similar to the ‘AdventureWorks Tabular Model 2012.

SQL Server Analysis Services Product Samples
SQL Server Analysis Services provides, a unified and integrated view of all your business data as the foundation for all of your traditional reporting, online analytical processing (OLAP) analysis, Key Performance Indicator (KPI) scorecards, and data mining.

Analysis Services Samples for SQL Server 2008 R2
This release is dedicated to the samples that ship for Microsoft SQL Server 2008R2. For many of these samples you will also need to download the AdventureWorks family of databases.

SQL Server Reporting Services Product Samples
This project contains Reporting Services samples released with Microsoft SQL Server product. These samples are in the following five categories: Application Samples, Extension Samples, Model Samples, Report Samples, and Script Samples. If you are interested in contributing Reporting Services samples, please let us know by posting in the developers’ forum.

Reporting Services Samples for SQL Server 2008 R2
This release is dedicated to the samples that ship for Microsoft SQL Server 2008 R2 PCU1. For many of these samples you will also need to download the AdventureWorks family of databases.

SQL Server Integration Services Product Samples
This project contains Integration Services samples released with Microsoft SQL Server product. These samples are in the following two categories: Package Samples and Programming Samples. If you are interested in contributing Integration Services samples, please let us know by posting in the developers’ forum.

Integration Services Samples for SQL Server 2008 R2
This release is dedicated to the samples that ship for Microsoft SQL Server 2008R2. For many of these samples you will also need to download the AdventureWorks family of databases.

Windows Azure SQL Reporting Admin Sample
The SQLReportingAdmin sample for Windows Azure SQL Reporting demonstrates the usage of SQL Reporting APIs, and manages (add/update/delete) permissions of SQL Reporting users.

Windows Azure SQL Reporting ReportViewer-SOAP API usage sample
These sample projects demonstrate how to embed a Microsoft ReportViewer control that points to reports hosted on SQL Reporting report servers and how to use SQL Reporting SOAP APIs in your Windows Azure Web application.

Enterprise Library 5.0 – Integration Pack for Windows Azure
This NuGet package contains a zip file with the source code for the Enterprise Library Integration Pack for Windows Azure. 

Reference: Pinal Dave (http://blog.sqlauthority.com)