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 table_22170495_7 (top_50_ranking VARCHAR, original_airing VARCHAR)

### Question ###
How many of the episodes in the top 50 rankings were originally aired on June 28, 2010?

### Accurate SQL ###

SELECT COUNT(top_50_ranking) FROM table_22170495_7 WHERE original_airing = "June 28, 2010"