how many teams have used the stadium which hosted the judo at the 2008 summer olympics – women's 52 kg ?
SELECT DISTINCT COUNT attr_open var_uri attr_close where brack_open dbr_Judo_at_the_2008_Summer_Olympics_–_Women's_52_kg dbp_venue var_x sep_dot var_x dbo_tenant var_uri sep_dot var_x a dbo_Stadium brack_close