--------
0	1	x=0
1	0	x<>0
3	0	x<>0
\N	\N	x<>0
--------
2020-01-01		2	0	leave
2020-01-02	aaa	0	1	delete
2020-01-03		2	0	leave
2020-01-04		2	0	leave
2020-01-05	\N	2	0	leave
2020-01-06	aaa	0	1	delete
2020-01-07	aaa	0	1	delete
2020-01-08	aaa	\N	\N	leave
--------
2020-01-01		2
2020-01-03		2
2020-01-04		2
2020-01-05	\N	2
2020-01-08	aaa	\N