mybatis sql中的标签

1. isEqual

        select sum(cou) from (
            select count(*) cou from TABLE_NAME_a T
            where 1=1
            <isEqual property = "type" compareValue="xxx">
                and T.aa_type = #{aaType}
            </isEqual>

            union all

            select count(*) cou from TABLE_NAME_b T
            where 1=1
            <isEqual property = "type" compareValue="xxx">
                and T.aa_type = #{aaType}
            </isEqual>
        )