Hash Table Implementation | Dataford Interview Questions

Implement a Hash Table without using any inbuilt map.

Asked in the Technical Round 2 stage. Represent the hash table with relational tables, assign each key to a bucket, and retrieve values while correctly handling collisions and missing keys.

Output

One row per lookup request with request_id, lookup_key, and stored_value.
Return NULL for keys that are not present or whose stored value is NULL.
Order by request_id ascending.

Schema

hash_buckets

Column	Type	Description
bucket_idPK	INT	Identifier for a hash bucket

hash_entries

Column	Type	Description
entry_idPK	INT	Unique identifier for a stored entry
bucket_id	INT	Bucket containing the entry
entry_key	VARCHAR(50)	Stored hash table key
entry_value	INT	Value stored for the key

lookup_requests

Column	Type	Description
request_idPK	INT	Unique lookup request identifier
lookup_key	VARCHAR(50)	Key to retrieve

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