# Query a DynamoDB table with a complex filter expression with an AWS SDK
<a name="example_dynamodb_Scenarios_QueryWithComplexFilter_section"></a>

The following code examples show how to query a table with a complex filter expression.
+ Apply complex filter expressions to query results.
+ Combine multiple conditions using logical operators.
+ Filter items based on non-key attributes.

------
#### [ Java ]

**SDK for Java 2.x**  
Query a DynamoDB table with a complex filter expression using AWS SDK for Java 2.x.  

```
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
import software.amazon.awssdk.services.dynamodb.model.DynamoDbException;
import software.amazon.awssdk.services.dynamodb.model.QueryRequest;
import software.amazon.awssdk.services.dynamodb.model.QueryResponse;
import software.amazon.awssdk.services.dynamodb.model.ResourceNotFoundException;

import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

    public QueryResponse queryWithComplexFilter(
        final String tableName,
        final String partitionKeyName,
        final String partitionKeyValue,
        final String statusAttrName,
        final String activeStatus,
        final String pendingStatus,
        final String priceAttrName,
        final double minPrice,
        final double maxPrice,
        final String categoryAttrName) {

        // Validate parameters
        CodeSampleUtils.validateTableParameters(tableName, partitionKeyName, partitionKeyValue);
        CodeSampleUtils.validateStringParameter("Status attribute name", statusAttrName);
        CodeSampleUtils.validateStringParameter("Active status", activeStatus);
        CodeSampleUtils.validateStringParameter("Pending status", pendingStatus);
        CodeSampleUtils.validateStringParameter("Price attribute name", priceAttrName);
        CodeSampleUtils.validateStringParameter("Category attribute name", categoryAttrName);
        CodeSampleUtils.validateNumericRange("Minimum price", minPrice, 0.0, Double.MAX_VALUE);
        CodeSampleUtils.validateNumericRange("Maximum price", maxPrice, minPrice, Double.MAX_VALUE);

        // Create expression attribute names for the column names
        final Map<String, String> expressionAttributeNames = new HashMap<>();
        expressionAttributeNames.put("#pk", partitionKeyName);
        expressionAttributeNames.put(EXPRESSION_ATTRIBUTE_NAME_STATUS, statusAttrName);
        expressionAttributeNames.put(EXPRESSION_ATTRIBUTE_NAME_PRICE, priceAttrName);
        expressionAttributeNames.put(EXPRESSION_ATTRIBUTE_NAME_CATEGORY, categoryAttrName);

        // Create expression attribute values for the column values
        final Map<String, AttributeValue> expressionAttributeValues = new HashMap<>();
        expressionAttributeValues.put(
            ":pkValue", AttributeValue.builder().s(partitionKeyValue).build());
        expressionAttributeValues.put(
            EXPRESSION_ATTRIBUTE_VALUE_ACTIVE,
            AttributeValue.builder().s(activeStatus).build());
        expressionAttributeValues.put(
            EXPRESSION_ATTRIBUTE_VALUE_PENDING,
            AttributeValue.builder().s(pendingStatus).build());
        expressionAttributeValues.put(
            EXPRESSION_ATTRIBUTE_VALUE_MIN_PRICE,
            AttributeValue.builder().n(String.valueOf(minPrice)).build());
        expressionAttributeValues.put(
            EXPRESSION_ATTRIBUTE_VALUE_MAX_PRICE,
            AttributeValue.builder().n(String.valueOf(maxPrice)).build());

        // Create the query request
        final QueryRequest queryRequest = QueryRequest.builder()
            .tableName(tableName)
            .keyConditionExpression(KEY_CONDITION_EXPRESSION)
            .filterExpression(FILTER_EXPRESSION)
            .expressionAttributeNames(expressionAttributeNames)
            .expressionAttributeValues(expressionAttributeValues)
            .build();

        return dynamoDbClient.query(queryRequest);
    }
```
+  For API details, see [Query](https://docs.aws.amazon.com/goto/SdkForJavaV2/dynamodb-2012-08-10/Query) in *AWS SDK for Java 2.x API Reference*. 

------
#### [ JavaScript ]

**SDK for JavaScript (v3)**  
Query a DynamoDB table with a complex filter expression using AWS SDK for JavaScript.  

```
const { DynamoDBClient, QueryCommand } = require("@aws-sdk/client-dynamodb");

/**
 * Queries a DynamoDB table with a complex filter expression
 * 
 * @param {Object} config - AWS SDK configuration object
 * @param {string} tableName - The name of the DynamoDB table
 * @param {string} partitionKeyName - The name of the partition key
 * @param {string} partitionKeyValue - The value of the partition key
 * @param {number|string} minViews - Minimum number of views for filtering
 * @param {number|string} minReplies - Minimum number of replies for filtering
 * @param {string} requiredTag - Tag that must be present in the item's tags set
 * @returns {Promise<Object>} - The query response
 */
async function queryWithComplexFilter(
  config,
  tableName,
  partitionKeyName,
  partitionKeyValue,
  minViews,
  minReplies,
  requiredTag
) {
  try {
    // Create DynamoDB client
    const client = new DynamoDBClient(config);

    // Construct the query input
    const input = {
      TableName: tableName,
      KeyConditionExpression: "#pk = :pkValue",
      FilterExpression: "views >= :minViews AND replies >= :minReplies AND contains(tags, :tag)",
      ExpressionAttributeNames: {
        "#pk": partitionKeyName
      },
      ExpressionAttributeValues: {
        ":pkValue": { S: partitionKeyValue },
        ":minViews": { N: minViews.toString() },
        ":minReplies": { N: minReplies.toString() },
        ":tag": { S: requiredTag }
      }
    };

    // Execute the query
    const command = new QueryCommand(input);
    return await client.send(command);
  } catch (error) {
    console.error(`Error querying with complex filter: ${error}`);
    throw error;
  }
}
```
+  For API details, see [Query](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/client/dynamodb/command/QueryCommand) in *AWS SDK for JavaScript API Reference*. 

------
#### [ Python ]

**SDK for Python (Boto3)**  
Query a DynamoDB table with a complex filter expression using AWS SDK for Python (Boto3).  

```
import boto3
from boto3.dynamodb.conditions import Attr, Key


def query_with_complex_filter(
    table_name,
    partition_key_name,
    partition_key_value,
    min_rating=None,
    status_list=None,
    max_price=None,
):
    """
    Query a DynamoDB table with a complex filter expression.

    Args:
        table_name (str): The name of the DynamoDB table.
        partition_key_name (str): The name of the partition key attribute.
        partition_key_value (str): The value of the partition key to query.
        min_rating (float, optional): Minimum rating value for filtering.
        status_list (list, optional): List of status values to include.
        max_price (float, optional): Maximum price value for filtering.

    Returns:
        dict: The response from DynamoDB containing the query results.
    """
    # Initialize the DynamoDB resource
    dynamodb = boto3.resource("dynamodb")
    table = dynamodb.Table(table_name)

    # Start with the key condition expression
    key_condition = Key(partition_key_name).eq(partition_key_value)

    # Initialize the filter expression and expression attribute values
    filter_expression = None
    expression_attribute_values = {}

    # Build the filter expression based on provided parameters
    if min_rating is not None:
        filter_expression = Attr("rating").gte(min_rating)
        expression_attribute_values[":min_rating"] = min_rating

    if status_list and len(status_list) > 0:
        status_condition = None
        for i, status in enumerate(status_list):
            status_value_name = f":status{i}"
            expression_attribute_values[status_value_name] = status

            if status_condition is None:
                status_condition = Attr("status").eq(status)
            else:
                status_condition = status_condition | Attr("status").eq(status)

        if filter_expression is None:
            filter_expression = status_condition
        else:
            filter_expression = filter_expression & status_condition

    if max_price is not None:
        price_condition = Attr("price").lte(max_price)
        expression_attribute_values[":max_price"] = max_price

        if filter_expression is None:
            filter_expression = price_condition
        else:
            filter_expression = filter_expression & price_condition

    # Prepare the query parameters
    query_params = {"KeyConditionExpression": key_condition}

    if filter_expression:
        query_params["FilterExpression"] = filter_expression
        if expression_attribute_values:
            query_params["ExpressionAttributeValues"] = expression_attribute_values

    # Execute the query
    response = table.query(**query_params)
    return response


def query_with_complex_filter_and_or(
    table_name,
    partition_key_name,
    partition_key_value,
    category=None,
    min_rating=None,
    max_price=None,
):
    """
    Query a DynamoDB table with a complex filter expression using AND and OR operators.

    Args:
        table_name (str): The name of the DynamoDB table.
        partition_key_name (str): The name of the partition key attribute.
        partition_key_value (str): The value of the partition key to query.
        category (str, optional): Category value for filtering.
        min_rating (float, optional): Minimum rating value for filtering.
        max_price (float, optional): Maximum price value for filtering.

    Returns:
        dict: The response from DynamoDB containing the query results.
    """
    # Initialize the DynamoDB resource
    dynamodb = boto3.resource("dynamodb")
    table = dynamodb.Table(table_name)

    # Start with the key condition expression
    key_condition = Key(partition_key_name).eq(partition_key_value)

    # Build a complex filter expression with AND and OR operators
    filter_expression = None
    expression_attribute_values = {}

    # Build the category condition
    if category:
        filter_expression = Attr("category").eq(category)
        expression_attribute_values[":category"] = category

    # Build the rating and price condition (rating >= min_rating OR price <= max_price)
    rating_price_condition = None

    if min_rating is not None:
        rating_price_condition = Attr("rating").gte(min_rating)
        expression_attribute_values[":min_rating"] = min_rating

    if max_price is not None:
        price_condition = Attr("price").lte(max_price)
        expression_attribute_values[":max_price"] = max_price

        if rating_price_condition is None:
            rating_price_condition = price_condition
        else:
            rating_price_condition = rating_price_condition | price_condition

    # Combine the conditions
    if rating_price_condition:
        if filter_expression is None:
            filter_expression = rating_price_condition
        else:
            filter_expression = filter_expression & rating_price_condition

    # Prepare the query parameters
    query_params = {"KeyConditionExpression": key_condition}

    if filter_expression:
        query_params["FilterExpression"] = filter_expression
        if expression_attribute_values:
            query_params["ExpressionAttributeValues"] = expression_attribute_values

    # Execute the query
    response = table.query(**query_params)
    return response
```
+  For API details, see [Query](https://docs.aws.amazon.com/goto/boto3/dynamodb-2012-08-10/Query) in *AWS SDK for Python (Boto3) API Reference*. 

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For a complete list of AWS SDK developer guides and code examples, see [Using DynamoDB with an AWS SDK](sdk-general-information-section.md). This topic also includes information about getting started and details about previous SDK versions.