选择查询时,我需要从Table2的值替换Table1的字段值.
例如:
表格1:
Org Permission
--------------------------------------
Company1 1,3,7
Company2 1,3,8
表2:
Permission Permission
--------------------------------------
1 Read
3 Write
7 Execute
8 Delete
我需要这样:
Org Permission
--------------------------------------
Company1 Read,Write,Execute
Company2 Read,Write,Delete
解决方法:
如果您不想更新现有表,而只想选择数据,则可以使用这种费力的查询.
http://sqlfiddle.com/#!4/22909/4
WITH changed_table AS
(SELECT val1, EXTRACTVALUE (x.COLUMN_VALUE, 'e') val2new
FROM (SELECT val1, val2 xml_str
FROM table1),
TABLE (XMLSEQUENCE (XMLTYPE ( '<e><e>'
|| REPLACE (xml_str, ',', '</e><e>')
|| '</e></e>'
).EXTRACT ('e/e')
)
) x)
SELECT ct.val1, listagg(table2.val2,',') within group (order by table2.val2) val2
FROM changed_table ct, table2 table2
WHERE ct.val2new = table2.val1
group by ct.val1;
我已经使用XMLTYPE将逗号分隔的数字分隔为行.然后将行与第二个表连接起来以获得描述,最后使用LISTAGG函数形成逗号分隔的字符串.不知道此查询的效率如何.我同意马克·班尼斯特的评论.