如何给recyclerView瀑布流设置均等间距

 FULL JOIN (SELECT
               TABLENAME = B.NAME,
               FIELDNAME = A.NAME,
               FIELDSNO = A.COLID,
               FIELDTYPE = C.NAME,
               LENGTH = A.LENGTH,
               LENSEC = A.XSCALE,
               ALLOWNULL = A.ISNULLABLE
             FROM INTFSIMS..SYSCOLUMNS A
               LEFT JOIN INTFSIMS..SYSOBJECTS B
                 ON A.ID = B.ID
               LEFT JOIN INTFSIMS..SYSTYPES C
                 ON A.XUSERTYPE = C.XUSERTYPE
             WHERE B.XTYPE = 'U') B
    ON A.TABLENAME = B.TABLENAME
      AND A.FIELDNAME = B.FIELDNAME