介绍to_char(数字, 格式),比较常用的格式 9 表示有效位数 0 用0补足位数 B 用空格补足位数 原数的位置有实际数字占位的时候,0和9的效果是一样的。 0和9的区别在于格式中的那一位置实际数字没有站位的情况下。 select to_char(0.45,'0.99'); 结果是0.45 sel
介绍to_char(数字, ‘格式’),比较常用的格式
9 表示有效位数
0 用0补足位数
B 用空格补足位数
原数的位置有实际数字占位的时候,0和9的效果是一样的。
0和9的区别在于格式中的那一位置实际数字没有站位的情况下。
select to_char(0.45,'0.99'); 结果是0.45
select to_char(0.45,'9.99'); 结果是.45
select to_char(2.45,'0.99'); 结果是2.45
select to_char(2.45,'9.99'); 结果是2.45
因为0.45的有效数字是小数点后第一位,小数点前没有有效数字,改为如果想要显示的话,就要用0来补充位数。
例子:
<span>SELECT</span> to_char<span>(</span><span>123.45</span><span>,</span> <span>'0009.9'</span><span>)</span><span>,</span> to_char<span>(</span><span>123.45</span><span>,</span> <span>'9999.9'</span><span>)</span><span>,</span> to_char<span>(</span><span>123.45</span><span>,</span> <span>'B999.9'</span><span>)</span> <span>FROM</span> dual;
结果为
TO_CHAR(123.45,'0009.9') TO_CHAR(123.45,'9999.9') TO_CHAR(123.45,'B999.9') ------------------------ ------------------------ ------------------------ 0123.5 123.5 123.5

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