mybatis嵌套查询

嵌套查询，第⑤行的查询条件是
第⑤行_{第⑥行作为一个临时表，需要为临时表指定别名，这里的zd和FB都是别名，否则会报错。如果第⑤行}第⑥行查询的只有一列，那么第②行就不能查除了这列的其他列了；第⑤行~第⑥行查询的有a,b,c,d列，那么第②行只可以查询a,b,c,d这四列里的任意，不可以查询e,f列

[Err] 1248 - Every derived table must have its own alias  

    
①    SELECT
②   *
③       FROM
④   (
⑤       SELECT
            A .USERNAME AS userName,
            A .STAFF_ID AS zdStaffId,
            A .STAFF_NAME AS zdStaffName,
            A .MOBILE_TEL AS zdPhone,
            b.JOB_ID AS zdJobId,
            c.ORG_ID AS zdOrgId,
            G .ORG_NAME AS zdOrgName,
            A .CERT_NO AS zdIDCordNum
        FROM
            NM_TBK.UOS_STAFF_CNST A,
            NM_TBK.UOS_JOB_STAFF_CNST b,
            NM_TBK.UOS_JOB_CNST c,
            NM_TBK.UOS_ORG_CNST G
        WHERE
            2 > ROWNUM
        AND A .STATE = 1
        AND b.STATE = 1
        AND b.IS_NORMAL = 1
        AND b.ISBASIC = 1
        AND c.STATE = 1
        AND G .STATE = 1
        AND c.ORG_ID = G .ORG_ID
        AND b.JOB_ID = c.JOB_ID
        AND A .STAFF_ID = b.STAFF_ID
        AND A .USERNAME = #{0}
⑥           ) zd
      LEFT JOIN (
        SELECT
        D .USERNAME,
        D .STAFF_ID AS fbStaffId,
        D .STAFF_NAME AS fbStaffName,
        D .MOBILE_TEL AS fbPhone,
        E .JOB_ID AS fbJobId,
        f.ORG_ID AS fbOrgId,
        H .ORG_NAME AS fbOrgName,
        D .CERT_NO AS fbIDCordNum
    FROM
        NM_TBK.UOS_STAFF_SAS D,
        NM_TBK.UOS_JOB_STAFF_SAS E,
        NM_TBK.UOS_JOB_SAS f,
        NM_TBK.UOS_ORG_SAS H
    WHERE
        2 > ROWNUM
    AND D .STATE = 1
    AND E .STATE = 1
    AND E .IS_NORMAL = 1
    AND E .ISBASIC = 1
    AND f.STATE = 1
    AND H .STATE = 1
    AND f.ORG_ID = H .ORG_ID
    AND E .JOB_ID = f.JOB_ID
    AND D .STAFF_ID = E .STAFF_ID
    AND D .USERNAME = #{0}
) FB ON ZD.USERNAME = FB.USERNAME