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_26258348_4 ( winning_constructor VARCHAR, fastest_lap VARCHAR )

### Question ###
How many winning constructor catagories are there when Mark Webber had the fastest lap?

### Accurate SQL ###

SELECT COUNT(winning_constructor) FROM table_26258348_4 WHERE fastest_lap = "Mark Webber"