oracle中转换函数问题

Question

在sql server中这样的cast(v_level as char(2)) 的函数,在oracle中用to_char()函数,但在oracle中to_char(),我只知道日期转换成字符,象to_char(sysdate,'yyyy-mm-dd'),但是怎样把 v_level( 是number型的)转换为char型?

Answer 1

直接
select to_char(v_level) from tab

Answer 2

那cast(v_level as char(2)) 用to_char(v_level)不限制位数了

Answer 3

需要怎么限制呢?只取前面或后面的两位吗?可以用substr 函数

Answer 4

用格式符'9999'或'000'，0为空位补0，9为不补
SQL> select to_char(999.12345,'00000.9999') from dual;TO_CHAR(999.12345,'00000.9999'
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 00999.1235SQL> select to_char(999.12345,'99999.9999') from dual;TO_CHAR(999.12345,'99999.9999'
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   999.1235SQL> select to_char(999.12345,'99999.999') from dual;TO_CHAR(999.12345,'99999.999')
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   999.123