User`s guide

7 Functions — Alphabetical List
7-86
Using DatabaseDatastore Objects
Access collection of data stored in database
MATLAB has various datastores that let you import large data sets into MATLAB for
analysis. A DatabaseDatastore object is a type of datastore that contains the resulting
data from executing an SQL query in a relational database.
With a DatabaseDatastore object, you can perform these tasks:
• Preview data.
• Read data in chunks.
• Read every record in the data set.
• Reset the cursor position to the start of the data set.
• Continue reading data until the cursor position reaches the end of the data set.
• Analyze a large data set stored in a database using MapReduce.
After creating a DatabaseDatastore object, you can write custom functions to run
MapReduce. For details, see “Getting Started with MapReduce”.
Examples
Create a DatabaseDatastore Object
Connect to a Microsoft SQL Server database with Windows Authentication. This code
assumes you are creating a database connection conn using the native ODBC interface
with the authenticated ODBC data source name MS SQL Server Auth and blank user
name and password.
conn = database.ODBCConnection('MS SQL Server Auth','','');
Create a DatabaseDatastore object dbds using the database connection conn and
SQL query sqlquery. This SQL query retrieves all products from the product table
productTable ordered by product number.
sqlquery = ['select * from [toy_store].[dbo].[productTable] '...
'order by productNumber'];