| layout | topic | title | language |
|---|---|---|---|
exercise |
Aggregation |
SUM |
SQL |
Write a query that returns the number of individuals of each species
captured in each year (total_abundance) and the total_biomass of those
individuals (the sum of the weight). The units for biomass should be in
kilograms. Include the year and species_id in the output. Sort the result
chronologically by year and then alphabetically by species. Save as
mass_abundance_data.