Table schema:
CREATE TABLE table_name_31 (team__b_ VARCHAR, match_date VARCHAR, s_no VARCHAR, margin VARCHAR)

Question: What is Team (B), when S No is less than 18, when Margin is 8 Wickets, and when Match Date is Oct 30, 1989?
SQL: SELECT team__b_ FROM table_name_31 WHERE s_no < 18 AND margin = "8 wickets" AND match_date = "oct 30, 1989"