The hike database contains hikes that have 2 attributes: a hikeid and a name.
A hike can have multiple land types (cascades, forest, meadow...).
A hike doesn't need to have a land type.
A user can give one (and one only) rate to a hike.
This rating can be a value between 0 and 5 stars, without decimals.
A user can also label a hike on a specific date that the system offers (e.g. "very cool", "amazing", "breath taking"...).
He can label the same hike many times, at different moments.
Here is the entity-relation model that needs to be implemented:
You need to respect certain constraint on the data. Here are constraints on types for each tables:
users: userid (int) [PK], username (text)hikes: hikeid (int) [PK], hikename (text)ratings: userid (int) [FK], hikeid (int) [FK], rating (int [0-5]), timestamp (bigint)landtypes: landid (int) [PK], landtype (text)label: labelid (int) [PK], labelinfo (text)hasalandtype: hikeid (int)[FK], landid [FK]haslabeled: userid (int) [FK], hikeid(int)[FK], labelid (int) [FK], timestamp (bigint)
[PK] stands for Primary Key [FK] stands for Foreign Key