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Data Extraction methods in Azure Synapse Analytics


Data extraction is an essential step in the data analysis process, and Azure Synapse Analytics provides a variety of methods to extract data from different sources. In this blog post, we will explore the different data extraction methods available in Azure Synapse Analytics and provide example codes to demonstrate how to use them.

Copy Data Transformation: Copy Data transformation is the most basic and commonly used method for extracting data in Azure Synapse Analytics. It allows you to copy data from a source to a sink, such as an Azure Data Lake Storage or an Azure SQL Database. The "Copy Data" transformation also allows for filtering and sorting of the data, as well as mapping columns to different names.

Example code:

{
    "name": "CopyData1",
    "properties": {
        "type": "Copy",
        "source": {
            "type": "SqlSource",
            "sqlReaderQuery": "SELECT * FROM mytable"
        },
        "sink": {
            "type": "AzureDataLakeStorageSink",
            "folderPath": "myfolder/mydata"
        }
    }
}

In this example, the "sqlReaderQuery" parameter specifies the SQL query to be used to extract the data from the Azure SQL Database. The "folderPath" parameter specifies the location in the Azure Data Lake Storage where the data will be copied to.

Data Flow Source: The Data Flow Source is a method of extracting data directly from a data flow. This method is useful when you want to extract data from a data flow that has already been transformed and cleaned.

Example code:

{
    "name": "DataFlowSource1",
    "properties": {
        "type": "DataFlowSource",
        "dataFlow": {
            "referenceName": "MyDataFlow"
        }
    }
}

In this example, the "referenceName" parameter specifies the name of the data flows that the data that will be extracted from.

Stored Procedure: The Stored Procedure method allows you to extract data by executing a stored procedure in an Azure SQL Database or an Azure Synapse Analytics SQL pool. This method is useful when you want to extract data from a specific stored procedure or when you want to pass parameters to the stored procedure.

Example code:

{
    "name": "StoredProcedure1",
    "properties": {
        "type": "SqlSource",
        "storedProcedureName": "sp_getdata",
        "storedProcedureParameters": [
            {
                "name": "param1",
                "value": "value1"
            },
            {
                "name": "param2",
                "value": "value2"
            }
        ]
    }
}

In this example, the "storedProcedureName" parameter specifies the name of the stored procedure to be executed and the "storedProcedureParameters" parameter specifies the parameters to be passed to the stored procedure.

Lookup Transformation: Lookup Transformation allows you to extract data from a reference data source by looking up values in the reference data source. This method is useful when you want to extract data that is stored in a reference data source, such as a CSV file or an Azure SQL Database.

Example code:

{
    "name": "Lookup1",
    "properties": {
        "


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