The union fields must be the same. You can add a field (number of people entering the site) to the result of the first picture as 0. The sql statement is as follows (select time_start, time_end,0 as num from table) union (select time_start, time_end, num from table ); num refers to the number of people entering the station
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UNION
The union fields must be the same. You can add a field (number of people entering the site) to the result of the first picture as 0. The
sql statement is as follows (select time_start, time_end,0 as num from table) union
(select time_start, time_end, num from table );
num refers to the number of people entering the station