D-23-SQL-집계함수

1. COUNT
   

select count(*) from police_station;
select count(distinct police_station) from crime_status;

2. SUM

select sum(case_number) from crime_status where status_type='발생';

3. AVG

select avg(case_number) from crime_status where police_station = '중부';

4. MIN , MAX

select min(case_number) from crime_status where status_type like '%발생%' and crime_type like '%강도%';
select max(case_number) from crime_status where status_type like '%발생%' and crime_type like '%강도%';