DELETE FROM "im_private_message";
DELETE FROM "im_group_message";
DELETE FROM "im_group";
DELETE FROM "im_group_member";
DELETE FROM "im_friend";
DELETE FROM "im_friend_request";
DELETE FROM "im_group_request";
DELETE FROM "im_face_pack";
DELETE FROM "im_face_pack_item";
DELETE FROM "im_face_user_item";