Write a query to get hierarchical data from a table where a parent-child relationship is maintained by ID and parent ID in the same table.

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Query to retrieve hierarchical data from a table with parent-child relationship maintained by ID and parent ID.

Use a self-join to join the table with itself based on the parent ID and ID columns.
Use a recursive CTE (Common Table Expression) to traverse the hierarchy and retrieve all levels of data.
Order the results by the hierarchy level to display the data in a hierarchical structure.