Answer Happy

Question 27 2 pts Consider the scenario where you have loaded the statistical neighbourhoods of Australia - with names and the exact geometries of their boundaries - into a PostgreSQL database using PostGIS. You also have indexed the spatial attribute. The schema looks as follows: CREATE TABLE Neighbourhoods AS ( area_id INTEGER, area_name VARCHAR(20), boundary GEOMETRY); CREATE INDEX BoundaryIndex ON Neighbourhoods USING GIST (boundary); We further frequently run the following spatial join query that combines data from the Neighbourhoods and the Landmarks tables: SELECT L.name FROM Landmarks L, Neighbourhoods N WHERE ST_Contains (N.boundary, L.location) AND N.area_id=4711; How is this query affected if we would drop the index BoundaryIndex? O The query will run slower because the database has to test now all neighbourhood boundaries rather than to filter them on their indexed bounding boxes first. O Without the index, the spatial join query will not work anymore. O The query will run faster because the index will not be needed to be updated too. O There will be no difference, because the query does not use this index.