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Chained data using single SQL Query (Fixed Length)

In e-commerce sites and in other applications, database sometimes will be designed in such a way that single table has child records in a chained fashion. Like, while defining a Product Type, Category and Sub-Category. A Sub-Category points to a Category in a same table and Category points to a Product Type in a same table. This Chained table has a format of Grand Parent, Parent and Child in same table as:

id parent_id name
1 0 John
2 1 Jacob
3 2 James
4 0 Jessie
5 4 Jemimah
6 5 Julia

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