示例：
select 'select a.xh,a.dj,a.xzb from xsjbxxb a where a.xzb=' || chr(39) || a.xzb || chr(39) || ' order by dj desc for update;'
from xsjbxxb a
結果：
select a.xh,a.dj,a.xzb from xsjbxxb a where a.xzb='機191' order by dj desc for update;
select a.xh,a.dj,a.xzb from xsjbxxb a where a.xzb='自動化類195' order by dj desc for update;
select a.xh,a.dj,a.xzb from xsjbxxb a where a.xzb='印191' order by dj desc for update;
說明：
要顯示的字符串用一對單引號表示
連接字符串的運算符是 ||
chr（39）表示單引號