Postgresql to_number() 函数格式
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Postgresql to_number() function format
提问by 0bj3ct
I want to use postgresql to_number(numberString, format_mask). My numberString may contain leading zeros (I don't know the actual length of these zeros and the numberString in total). I want to trim these zeros and get the value as number.
我想使用 postgresql to_number(numberString, format_mask)。我的 numberString 可能包含前导零（我不知道这些零的实际长度和 numberString 的总数）。我想修剪这些零并将值作为数字。
I've read about this function hereand currently using the format:
select to_number('00005469', '9999999999')
But if the length of '9's is less than the length of the numberString then I can't get the correct number. How can I make this work without writing a long list of '9' in format_mask?
但是如果 '9's 的长度小于 numberString 的长度，那么我就无法得到正确的数字。如果不在 format_mask 中写入一长串“9”，我该如何完成这项工作？
回答by a_horse_with_no_name
You don't need to_number()for this. Just cast the string to an integer:
你不需要to_number()这个。只需将字符串转换为整数：
select '00005469'::integer;
or using standard SQL:
或使用标准 SQL：
select cast('00005469' as integer);
回答by mentole
use like this it is simple:
像这样使用很简单：
to_number(to_char(yournumber, '99'),'99')
to_number(to_char(yournumber, '99'),'99')
