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_19835 ( "Stage" real, "Winner" text, "General classification" text, "Points classification" text, "Mountains classification" text, "Combination classification" text, "Team classification" text )

### Question ###
How many teams have a combination classification of Alejandro Valverde and a Points classification of Alessandro Petacchi?

### Accurate SQL ###

SELECT COUNT("Team classification") FROM table_19835 WHERE "Combination classification" = 'Alejandro Valverde' AND "Points classification" = 'Alessandro Petacchi'