How to Add a Column in BigQuery

In this tutorial, we'll show you how to add a column to an existing table in Google BigQuery using the SQL commands and BigQuery's user-friendly console. Adding a column is an important operation for enhancing your data schema without the need to recreate or overwrite the table.

Method 1: Using the BigQuery Console

To add a column via the BigQuery Console, follow these steps:

• Open the BigQuery Console in the Google Cloud Console.
• Navigate to your dataset and select the table you want to modify.
• Click on the "Edit schema" button in the table details section.
• Scroll down to the "Schema" section and click on the "Add Field" button.
• Enter the name of the new column, its data type, and any other relevant attributes.
• Click "Save" to apply the changes.

Method 2: Using SQL Command

You can also use an SQL command to add a column. Here’s an example SQL query:

                                ALTER TABLE `project_id.dataset_id.table_id`
                                ADD COLUMN new_column_name STRING;
                                

In the above SQL command:

• project_id: Your Google Cloud project ID.
• dataset_id: The BigQuery dataset containing your table.
• table_id: The ID of the table where you want to add the column.
• new_column_name: The name of the column you're adding.
• STRING: The data type for the new column. You can choose from data types such as STRING, INT64, BOOL, etc.

Conclusion

Adding a column to your BigQuery table is a simple and effective way to modify your schema to meet evolving data requirements. Whether you prefer using the console or writing SQL queries, both methods are straightforward and provide flexibility in how you structure your data.