Mysql查询本月和上个月

MySql查询本月
select count(*) from tb_order where date_format( create_time, ‘%Y-%m’) = date_format(now(), ‘%Y-%m’)

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Mysql查询上个月
select count(*) from tb_order where period_diff(date_format(now(),’%Y%m’), date_format(create_time,’%Y%m’)) = 1