Postgresql：如果列以减号结尾，则删除文本字段中的最后一个字符
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Postgresql: Remove last char in text-field if the column ends with minus sign
提问by Chris
I want to remove the last char in a column if it ends with the minus sign. How could I do this in postgresql?
如果以减号结尾，我想删除列中的最后一个字符。我怎么能在 postgresql 中做到这一点？
For example:
例如：
sdfs-dfg4t-etze45z5z- => sdfs-dfg4t-etze45z5z
gsdhfhsfh-rgertggh => stay untouched
Is there an easy syntax I can use?
有我可以使用的简单语法吗？
回答by Jeremy Shimanek
Use the trim function if all trailing dashes can be removed, or use regexp_replace if you need only the last dash removed. Trim probably performs better than regexp_replace.
如果可以删除所有尾随破折号，请使用修剪功能，如果您只需要删除最后一个破折号，请使用 regexp_replace。Trim 的性能可能比 regexp_replace 好。
with strings as
(
select 'sdfs-dfg4t-etze45z5z-' as string union all
select 'sdfs-dfg4t-etze45z5z--' as string union all
select 'gsdhfhsfh-rgertggh'
)
select
string,
trim(trailing '-' from string) as all_trimmed,
regexp_replace(string, '-$', '') as one_trimmed
from
stringsResult:
结果：
string all_trimmed one_trimmed
sdfs-dfg4t-etze45z5z- sdfs-dfg4t-etze45z5z sdfs-dfg4t-etze45z5z
sdfs-dfg4t-etze45z5z-- sdfs-dfg4t-etze45z5z sdfs-dfg4t-etze45z5z-
gsdhfhsfh-rgertggh gsdhfhsfh-rgertggh gsdhfhsfh-rgertggh回答by Chris
use regexp_replace(your_field, '-+$', '');
用 regexp_replace(your_field, '-+$', '');
