A data analyst needs to upload a 5 MB comma-delimited CSV file to Databricks using only the Workspace UI — without writing any code or using the CLI. The file has a header row and several columns where the inferred data types are incorrect (for example, a column named order_id is inferred as DOUBLE instead of STRING, and order_date is inferred as STRING instead of DATE). Which statement CORRECTLY describes what the analyst can do during the UI upload workflow to fix the type issues before the table is created, and what format the table will be stored in?
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Correct answer: B
WHY B is correct: The Databricks Workspace UI upload wizard includes a schema preview and editing step where the analyst can see the parsed data sample and modify the inferred column types for any column before the table is created. Changing order_id from DOUBLE to STRING and order_date from STRING to DATE are both standard adjustments supported by the wizard. Column names can also be edited during this step. After the analyst confirms the schema and selects a target catalog and schema in Unity Catalog, Databricks stores the uploaded data as a managed Delta table — not as a CSV file. The Delta format provides ACID transactions, time travel, schema enforcement, and full SQL DML support immediately upon creation.
WHY NOT A: The upload wizard does parse data rows (not just the header) to infer column types, and it absolutely allows the analyst to change inferred types before the table is created — this is a key feature of the wizard. The resulting table is stored in Delta format, not CSV format. While post-upload ALTER COLUMN is possible in Delta, it is unnecessary if type corrections are made during the wizard.
WHY NOT C: The upload wizard does not lock in inferred types — column type overrides are explicitly supported as part of the schema editing step. Tables created through the wizard are stored in Delta format, not Parquet format. While Delta tables internally use Parquet files as the storage layer, the table format is Delta (with the transaction log), not raw Parquet.
WHY NOT D: The Databricks UI upload wizard creates a managed Delta table in Unity Catalog storage — it does not create an external table pointing to a CSV in DBFS. The wizard does not derive types from CSV header metadata alone; it infers types from actual data values. The 'column name suffix' date casting convention (order_date_DATE) is entirely fabricated and does not exist in Databricks.
WHY NOT E: The upload wizard supports type changes for all column types — including date and timestamp — not just numeric types. Users can select DATE, TIMESTAMP, STRING, INT, BOOLEAN, and other types from a dropdown during the schema editing step. Tables created via the wizard are standard managed Delta tables with full read/write DML support; there is no 'read-only' restriction, and no DEEP CLONE is required before performing DML.