---
title: "Analyze Data in Local Compute Context | Microsoft Docs"
ms.custom: ""
ms.date: "05/18/2017"
ms.prod: "sql-server-2016"
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ms.technology: 
  - "r-services"
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applies_to: 
  - "SQL Server 2016"
dev_langs: 
  - "R"
ms.assetid: 787bb526-4a13-40fa-9343-75d3bf5ba6a2
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author: "jeannt"
ms.author: "jeannt"
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---
# Analyze Data in Local Compute Context (Data Science Deep Dive)

Although it might be faster to run complex R code using the server context, sometimes it is just more convenient to get your data out of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] and analyze it on your private workstation.

In this section, you'll learn how to switch back to a local compute context, and move data between contexts to optimize performance.

## Create a Local Summary

1. Change the compute context to do all your work locally.
  
    ```R
    rxSetComputeContext ("local")
    ```
  
2. When extracting data from [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)], you can often get better performance by increasing the number of rows extracted for each read.  To do this, increase the value for the *rowsPerRead* parameter on the data source.
  
    ```R
    sqlServerDS1 <- RxSqlServerData(
       connectionString = sqlConnString,
       table = sqlFraudTable,
       colInfo = ccColInfo,
       rowsPerRead = 10000)
    ```
  
    Previously, the value of *rowsPerRead* was set to 5000.
  
3. Now, call **rxSummary** on the new data source.
  
    ```R
    rxSummary(formula = ~gender + balance + numTrans + numIntlTrans + creditLine, data = sqlServerDS1)
    ```
  
    The actual results should be the same as when you run rxSummary in the context of the [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] computer.  However, the operation might be faster or slower. Much depends on the connection to your database, because the data is being transferred to your local computer for analysis.


## Next  Step

[Move Data between SQL Server and XDF File](../../advanced-analytics/tutorials/deepdive-move-data-between-sql-server-and-xdf-file.md)

## Previous Step

[Perform Chunking Analysis using rxDataStep](../../advanced-analytics/tutorials/deepdive-perform-chunking-analysis-using-rxdatastep.md)