Create capital-gainloss.sql

Author: kamyu104

MySQL/capital-gainloss.sql

@@ -0,0 +1,11 @@
+# Time:  O(n)
+# Space: O(n)
+
+SELECT stock_name, 
+       Sum(CASE 
+             WHEN operation = 'Buy' THEN -price 
+             ELSE price 
+           END) AS capital_gain_loss 
+FROM   stocks 
+GROUP  BY stock_name 
+ORDER  BY NULL;