Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE tryout ( pid number, cname text, ppos text, decision text )
TABLE: CREATE TABLE college ( cname text, state text, enr number )
TABLE: CREATE TABLE player ( pid number, pname text, ycard text, hs number )

### Question ###
How many schools have some students playing in goalie and mid positions.

### Accurate SQL ###

SELECT COUNT(*) FROM (SELECT cname FROM tryout WHERE ppos = 'goalie' INTERSECT SELECT cname FROM tryout WHERE ppos = 'mid')