this question has answer here:
- explicit vs implicit sql joins 11 answers
so if i've asked following question:
write sql statement find list of customers appointed salesman jobs gets commission company more 12%
tables: customer
customer_id cust_name city grade salesman_id ----------- ------------ ---------- ---------- ----------- 3002 nick rimando new york 100 5001 3005 graham zusi california 200 5002 3001 brad guzan london 100 5005 3004 fabian johns paris 300 5006 3007 brad davis new york 200 5001 3009 geoff camero berlin 100 5003 3008 julian green london 300 5002 3003 jozy altidor moncow 200 5007 salesman
salesman_id name city commission ----------- ---------- ---------- ---------- 5001 james hoog new york 0.15 5002 nail knite paris 0.13 5005 pit alex london 0.11 5006 mc lyon paris 0.14 5003 lauson hen san jose 0.12 5007 paul adam rome 0.13 is there different between following ways it? if so, different? because end result same
if both same, why use ever inner join sentence? seams more difficult me first solution
select customer.cust_name, salesman.name, salesman.commission customer, salesman salesman.commission > 0.12 , customer.salesman_id = salesman.salesman_id -
select customer.cust_name, salesman.name, salesman.commission customer inner join salesman on customer.salesman_id = salesman.salesman_id salesman.commission > 0.12 thank much
the "more difficult" solution 1 you're not used to. of world uses inner join these days, if want write code more universally readable other programmers, should use inner join
