CREATE TABLE table_28172 ("No." FLOAT, "Title" CLOB, "Directed by" CLOB, "Written by" CLOB, "Original air date" CLOB, "Production code" CLOB, "U.S. viewers  ( million ) " CLOB)

What episode number was written by Anthony Sparks?
SELECT MIN("No.") FROM table_28172 WHERE "Written by" = 'Anthony Sparks'
SELECT MIN("No.") FROM "table_28172" WHERE "Written by" = 'Anthony Sparks'