I have been given an empty database that is in the process of being populated from various sources. Eventually the db will be used in a GIS and mapped.
My question is - could you help me understand how the following 3 tables work together. I am confused (escpecially with table 3) as how the information in entered and retrived.
Table 1: Barriers
barrier_type (input from variety of sources)
Table 2: Barrier_Type_Link
Description (this fields lists 15 possible barriers)
acronym (acronyms for barriers)
How does table 3 relate logically to table 1?
I think i am most confused as the purpose of and the way table 3 is supposed to work (did not create db). It appears that it is a sort of look up table for data entry - (no forms have been created yet for this db) since it lists a selection of barriers a user could pick from. I don't understand this table.
Yes, you are right - originally i had three tables - then on the advice of someone i dropped table 2 (link table)- because i needed a one to many relationship (a barrier can only have one type _ie" barrier can't be a culvert and a dam)
but i am still confused - think i might go back to the way it was -i think the person who created this db (with 3 tables) probably knows more than i do