Azure Table Storage Bindings

Integrate Azure Table Storage with Azure Functions for efficient NoSQL data operations.

Overview

Azure Functions provides powerful input and output bindings for Azure Table Storage, enabling seamless interaction with your tables directly from your function code. You can read entities from a table as input, or write entities to a table as an output.

Input Bindings

You can use Table Storage as an input binding to retrieve a single entity or a collection of entities from a table.

Retrieving a Single Entity

To retrieve a single entity, you typically specify the partition key and row key.

Example: C#
// function.json
{
  "bindings": [
    {
      "name": "inputBlob",
      "type": "blobTrigger",
      "direction": "in",
      "path": "input/{name}.txt",
      "connection": "AzureWebJobsStorage"
    },
    {
      "name": "tableEntity",
      "type": "table",
      "direction": "in",
      "tableName": "MyTable",
      "partitionKey": "MyPartition",
      "rowKey": "{name}",
      "connection": "AzureWebJobsStorage"
    },
    {
      "name": "outputBlob",
      "type": "blob",
      "direction": "out",
      "path": "output/{name}.txt",
      "connection": "AzureWebJobsStorage"
    }
  ]
}

// MyFunction.cs
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Host;
using System.IO;

public static class MyFunction
{
    public static void Run(Stream inputBlob, string tableEntity, TraceWriter log)
    {
        log.Info($"C# Blob trigger function processed");
        log.Info($"Table Entity: {tableEntity}");
        // Process tableEntity here
    }
}

Retrieving a Collection of Entities

For more complex queries or retrieving multiple entities, you can use a query expression.

Example: Python
# function_app.py
import azure.functions as func

app = func.FunctionApp()

@app.blob_trigger(path="input/{name}.txt",
                  connection="AzureWebJobsStorage")
@app.table_input(name="entities",
                 table_name="MyTable",
                 partition_key="MyPartition",
                 filter="RowKey ge '100'", # Example filter
                 connection="AzureWebJobsStorage")
@app.blob_output(path="output/{name}.txt",
                 connection="AzureWebJobsStorage")
def main(inputBlob: func.InputStream, entities: func.Table, outputBlob: func.Out[str]):
    logging.info(f"Python blob trigger function processed")
    for entity in entities:
        logging.info(f"Entity: {entity}")
    outputBlob.set("Processed")

Output Bindings

You can use Table Storage as an output binding to write entities to a table.

Example: JavaScript
// index.js
module.exports = async function (context, myQueueItem) {
    context.log('JavaScript queue trigger function processed work item', myQueueItem);

    const tableInsert = {
        partitionKey: "Orders",
        rowKey: myQueueItem.orderId,
        customerName: myQueueItem.customer,
        orderDate: new Date().toISOString(),
        amount: myQueueItem.total
    };

    context.bindings.tableOutput = tableInsert;
    context.log('Inserted into table.');
};

// function.json
{
  "bindings": [
    {
      "name": "myQueueItem",
      "type": "queueTrigger",
      "direction": "in",
      "queueName": "orders",
      "connection": "AzureWebJobsStorage"
    },
    {
      "name": "tableOutput",
      "type": "table",
      "direction": "out",
      "tableName": "Orders",
      "connection": "AzureWebJobsStorage"
    }
  ]
}

Configuration Options

Here are common configuration properties for Table Storage bindings:

Property Description Required
tableName The name of the table to interact with. Yes
partitionKey The partition key for single entity operations. Can use binding expressions. No (unless retrieving a single entity)
rowKey The row key for single entity operations. Can use binding expressions. No (unless retrieving a single entity)
filter An OData filter expression for querying entities (input bindings only). No
connection The name of an app setting that contains the Azure Storage connection string. Yes

Best Practices

For more detailed information, refer to the official Azure Table Storage documentation.

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