Weekly Store Hours and Redis Queries | Dataford Interview Questions

Given the opening and closing hours of a store in the week (format Mon-01..Sun-07 plus HHMM, e.g. StartTime=011000, EndTime=011700), find the list of all 5-minute-interval timestamps to query Redis; handle ranges that wrap past the end of the week.

Asked in the phone screen stage. Treat the opening timestamp as inclusive and the closing timestamp as exclusive.

Output

One row per store and five-minute timestamp, with columns store_id and timestamp_code.
Include valid non-null hour ranges, including weekly wraparound ranges.
Order by store_id, then chronological position within the week.

Schema

stores

Column	Type	Description
store_idPK	INT	Unique store identifier
store_name	VARCHAR(100)	Store display name

store_hours

Column	Type	Description
hours_idPK	INT	Unique opening-hours record
store_id	INT	Referenced store
start_time	VARCHAR(6)	Opening code containing a two-digit day and HHMM time
end_time	VARCHAR(6)	Exclusive closing code containing a two-digit day and HHMM time

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