用SQL实现其他进制到十进制的转换

-----二进制转换十进制-----------------
select sum(data1)
from (select substr('1101', rownum, 1) * power
                            (2, length('1101') - rownum) data1
from dual
connect by rownum <= length('1101'))

-----八进制转换十进制-----------------
select sum(data1)
from (select substr('1101', rownum, 1) * power
                            (8, length('1101') - rownum) data1
from dual
connect by rownum <= length('1101'))

-----十六进制转换十进制-----------------
select sum(data1)
from (select (CASE upper(substr('2D', rownum, 1))
WHEN 'A' THEN '10'
WHEN 'B' THEN '11'
WHEN 'C' THEN '12'
WHEN 'D' THEN '13'
WHEN 'E' THEN '14'
WHEN 'F' THEN '15'
ELSE substr('2D', rownum, 1)
END) * power(16, length('2D') - rownum) data1
from dual
connect by rownum <= length('2D'))

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