如何删除 SQL 中首字母缩略词中的空格？

Question

我想编写一个函数来删除孤立字母之间的空格，例如首字母缩略词。

例如，如果我有：

'I B M Computers' i need to have in return 'IBM Computers'
' I B M ' => 'IBM'
'Computers A B' => 'Computers AB'
'Computers A BC' => 'Computers A BC' (nothing changes)
'Computers A B CD' => 'Computers AB CD'
'Computers A B C D' => 'Computers ABCD'

我找不到正确的方法，有人可以帮我吗？

谢谢。

Answer 1

尝试使用 ltrim 和 rtrim 函数。例子：更新 'table' 设置 campo=ltrim(rtrim(campo))

Answer 2

使用替换函数去除比较两边的空格。

但请注意，这将是低效的，因为您的查询将无法使用索引

REPLACE(mystring,' ','')

https://docs.microsoft.com/en-us/sql/t-sql/functions/replace-transact-sql

Answer 3

本文 post 中描述的正则表达式应该适合您（对 MariaDB 的正则表达式稍作调整）。来自@Alan Moore 的post： "It looks to me like you want to remove any space that is (1) preceded by a letter which is not itself preceded by a letter, and (2) followed by a letter which is not itself followed by a letter. Those conditions can be expressed precisely as nested lookarounds"。请给他点赞

因此假设您的专栏名为 'DESC'，您的答案将是：

SELECT TRIM(REGEXP_REPLACE(DESC, '(?<=(?<![[:alpha:]])[[:alpha:]]) +(?=[[:alpha:]](?![[:alpha:]]))','')) AS fixed_desc
FROM table;

Test the regex here

如何删除 SQL 中首字母缩略词中的空格？

How to remove spaces in an acronym in SQL?

sql

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