Introduction
Dictionary database
Instruction
Okay, here comes the last exercise with this table!
Exercise
For each entry in the dictionary show the word, its direct hypernym and its hypernym's hypernym. Name the columns entry, hypernym and grandhypernym, respectively. Show all such entries, even those that don't have direct hypernyms or grandhypernyms.
Stuck? Here's a hint!
Use LEFT JOIN twice.
Type:
SELECT entry.word AS entry, hypernym.word AS hypernym, super_hypernym.word AS grandhypernym FROM dictionary AS entry LEFT JOIN dictionary AS hypernym ON entry.hypernym_id = hypernym.entry_id LEFT JOIN dictionary AS super_hypernym ON hypernym.hypernym_id = super_hypernym.entry_id
