In this task you are expected to fix an SQL query based on feedback. You will be given an SQL statement and an English description with what is wrong about that SQL statement. You must correct the SQL statement based off of the feedback. An SQL query works by selecting data from a table where certain conditions apply. A table contains columns where every row in that table must have a value for each column. Every table has a primary key that uniquely identifies each row, usually an id. To choose which columns are returned you specify that after the "SELECT" statement. Next, you use a "FROM" statement to specify what tables you want to select the data from. When you specify a table you can rename it with the "AS" statement. You can reference that table by whatever name follows the "AS" statement. If you want to select data from multiple tables you need to use the "JOIN" statement. This will join the tables together by pairing a row in one table with every row in the other table (Cartesian Product). To limit the number of rows returned you should use the "ON" statement. This will only return rows where the condition specified after the statement is true, this is usually an equals operator with primary keys. You can also use the "WHERE" statement to specify that only rows with column values statisfying a certain condition, should be returned. The "GROUP BY" statement will group rows together that have equal column values for whatever columns follows the statement. The "HAVING" statement will return groups that statisfy whatever condition follows the statement. Any column(s) being returned from grouped rows must either be an aggregate function, (AVG, MAX, COUNT, SUM, ...) of a column, or the column(s) that the data was grouped by. To sort the returned data you can use the "ORDER BY" command which will order the data by whatever aggregate function or column follows the statement. The "DESC" statement will sort in descending order and the "ASC" statement will sort in ascending order. Finally, you can use the "LIMIT" statement to return a certain number of rows. When "*" is used in an SQL statement every column is returned. For example, SELECT * FROM table WHERE attribute = 1, will select every column from rows with the attribute column equal to 1. 
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Question: SQL: SELECT Sum ( total ) FROM invoices WHERE billing_city = "Chicago"
Feedback: also make sure billing state equals IL

Answer: SELECT sum(total) FROM invoices WHERE billing_city  =  "Chicago" AND billing_state  =  "IL"


Question: SQL: SELECT Count ( * ) FROM Student AS T1 JOIN Dorm AS T2 JOIN Lives_in AS T3 ON T1.StuID = T3.stuid AND T3.dormid = T2.dormid WHERE T1.Sex = "Smith Hall" AND T2.gender = "F"
Feedback: There should be dorm name instead of sex and sex instead of gender .

Answer: SELECT count(*) FROM student AS T1 JOIN lives_in AS T2 ON T1.stuid  =  T2.stuid JOIN dorm AS T3 ON T3.dormid  =  T2.dormid WHERE T3.dorm_name  =  'Smith Hall' AND T1.sex  =  'F'


Question: SQL: SELECT Avg ( T2.credit_score ) FROM bank AS T1 JOIN customer AS T2 ON T2.branch_ID = T1.branch_ID JOIN loan AS T3 ON T1.branch_ID = T3.branch_ID WHERE T3.loan_type = "Mortgages"
Feedback: Not only loan type equals Mortgages but also every other loan type in loan table .

Answer:
SELECT avg(credit_score) FROM customer WHERE cust_id IN (SELECT cust_id FROM loan)