Error while Fetching Data from Mongo to QuickSight using Athena (COLUMN_NOT_FOUND Error)

Are you tired of encountering the dreaded COLUMN_NOT_FOUND error while trying to fetch data from MongoDB to Amazon QuickSight using Amazon Athena? You’re not alone! In this comprehensive guide, we’ll delve into the causes of this error and provide step-by-step solutions to get your data flowing smoothly.

What is the COLUMN_NOT_FOUND Error?

The COLUMN_NOT_FOUND error occurs when Athena cannot find a specific column in your MongoDB data that is required for the query. This error can manifest in various ways, including:

• Column not found in table/schema
• Unknown column in field list
• Column does not exist in the data source

This error is often triggered by mismatched column names, incorrect data types, or missing columns in your MongoDB collection.

Causes of the COLUMN_NOT_FOUND Error

Before we dive into the solutions, let’s explore the common causes of this error:

1. Inconsistent Column Names: Column names in your MongoDB collection might not match the ones used in your Athena query or QuickSight dataset.
2. Missing Columns: The column required for the query might not exist in your MongoDB collection or might be missing in some documents.
3. Incorrect Data Types: The data type of the column in your MongoDB collection might not match the expected data type in your Athena query or QuickSight dataset.
4. Schema Mismatches: The schema of your MongoDB collection might not align with the schema expected by Athena or QuickSight.

Step-by-Step Solutions

Now that we’ve covered the causes, let’s get to the solutions!

Solution 1: Verify Column Names

Double-check the column names in your MongoDB collection, Athena query, and QuickSight dataset. Ensure that they match exactly, including case sensitivity.

// Example MongoDB collection
{
  "_id" : ObjectId("..."),
  "productName" : "Product A",
  "price" : 19.99
}

// Example Athena query
SELECT 
  productName,
  price
FROM 
  mymongoDatabase.myCollection

In the example above, the column names in the MongoDB collection and Athena query match exactly.

Solution 2: Check for Missing Columns

Verify that the required columns exist in your MongoDB collection. You can use the following MongoDB command to check:

db.myCollection.find().forEach(function(doc) {
  print(doc);
})

This command will display the contents of each document in your collection, helping you identify missing columns.

Solution 3: Verify Data Types

Confirm that the data types of the columns in your MongoDB collection match the expected data types in your Athena query or QuickSight dataset. You can use the following MongoDB command to check data types:

db.myCollection.find().forEach(function(doc) {
  print(typeof doc.price);
})

In this example, the command checks the data type of the “price” column. Ensure that the data type matches the one expected by Athena or QuickSight.

Solution 4: Align Schemas

Validate that the schema of your MongoDB collection aligns with the schema expected by Athena or QuickSight. You can use the following Athena command to check the schema:

DESCRIBE mymongoDatabase.myCollection

This command displays the schema of the MongoDB collection in Athena. Compare this schema with the one expected by QuickSight to identify any mismatches.

Additional Troubleshooting Steps

If the above solutions don’t resolve the issue, try the following additional troubleshooting steps:

• Check for any typos or incorrect characters in your column names or table schema.
• Verify that your Athena query or QuickSight dataset is pointing to the correct MongoDB collection and database.
• Ensure that your MongoDB collection has the necessary permissions and access controls to allow Athena or QuickSight to read the data.

Conclusion

The COLUMN_NOT_FOUND error can be frustrating, but by following these step-by-step solutions, you should be able to identify and resolve the underlying causes. Remember to verify column names, check for missing columns, ensure data type consistency, and align your schemas. With these tips, you’ll be fetching data from MongoDB to QuickSight using Athena in no time!

Causes	Solutions
Inconsistent Column Names	Verify column names in MongoDB, Athena, and QuickSight
Missing Columns	Check for missing columns in MongoDB collection
Incorrect Data Types	Verify data types in MongoDB, Athena, and QuickSight
Schema Mismatches	Align schemas in MongoDB, Athena, and QuickSight

By following this comprehensive guide, you’ll be well on your way to resolving the COLUMN_NOT_FOUND error and successfully fetching data from MongoDB to QuickSight using Athena.

Here are 5 Questions and Answers about “Error while fetching data from mongo to QuickSight using Athena (COLUMN_NOT_FOUND Error)”

Frequently Asked Question

Error while fetching data from mongo to QuickSight using Athena? Don’t worry, we’ve got you covered! Here are some frequently asked questions and answers to help you troubleshoot the COLUMN_NOT_FOUND error.