小黑小波比.sql某字段累加1或者减1

1.需求:在表中某字段基础加1,当某字段为空,赋值为1,当某字段不为空,在基础上加1

update publisher set subcount=(case when subcount is null then 1 else subcount+1 end) where pcode=:pcode

加1:某字段=(case when 某字段 is null then 1(值) else 某字段+1)

减1:某字段=(case when 某字段 is null then 0(值) else 某字段-1)