Authentication Manager Design | Dataford Interview Questions

Design Authentication Manager (LeetCode 1797) with a constraint of 10^5 queries.

Asked in the Coding round stage. For this SQL version, process the ordered authentication operations and return the number of unexpired tokens whenever a count operation occurs. A token is valid only when its expiration time is strictly greater than the operation time. Generating an existing token replaces its expiration time, while renewing an expired or unknown token has no effect.

Output

One row per count operation with query_id, event_time, and active_token_count.
Include only count operations.
Order by query_id ascending.

Schema

auth_manager_config

Column	Type	Description
manager_idPK	INT	Authentication manager identifier
time_to_live	INT	Token lifetime in time units

auth_queries

Column	Type	Description
query_idPK	INT	Sequence identifier for an authentication operation
manager_id	INT	Authentication manager used by the operation
operation	VARCHAR(20)	Operation name: generate, renew, or count
token_id	VARCHAR(100)	Token affected by generate or renew
event_time	INT	Time at which the operation occurs

Your question is Authentication Manager Design. Start with the requirements and the two tables in the Question tab.

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