这条sql怎么写
select a01 from a 的结果有5行，结果分别为：,我要怎么实现查询的结果为
[解决办法]

select '(' 
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       ltrim(max(SYS_CONNECT_BY_PATH('''' 
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 t.a1 
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 '''', ',')), ',') 
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 ')' col
  from (select a1, rownum rn from t1) t
 start with t.rn = 1
connect by prior rn = rn - 1