如何在 Oracle 中不使用 Initcap 只转换首字母大写？
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How to convert only first letter uppercase without using Initcap in Oracle?
提问by jarlh
Is there a way to convert the first letter uppercase in Oracle SQl without using the Initcap Function?
有没有办法在不使用 Initcap 函数的情况下转换 Oracle SQl 中的第一个字母大写？
I have the problem, that I must work with the DISTINCT keyword in SQL clause and the Initcap function doesn′t work.
我有一个问题，我必须在 SQL 子句中使用 DISTINCT 关键字，而 Initcap 函数不起作用。
Heres is my SQL example:
这是我的 SQL 示例：
select distinct p.nr, initcap(p.firstname), initcap(p.lastname), ill.describtion
from patient p left join illness ill
on p.id = ill.id
where p.deleted = 0
order by p.lastname, p.firstname;
I get this error message: ORA-01791: not a SELECTed expression
我收到此错误消息：ORA-01791: not a SELECTed expression
回答by jarlh
When SELECT DISTINCT, you can't ORDER BYcolumns that aren't selected. Use column aliases instead, as:
当 时SELECT DISTINCT，您ORDER BY不能选择未选中的列。改用列别名，如：
select distinct p.nr, initcap(p.firstname) fname, initcap(p.lastname) lname, ill.describtion
from patient p left join illness ill
on p.id = ill.id
where p.deleted = 0
order by lname, fname
回答by davegreen100
this would do it, but i think you need to post your query as there may be a better solution
这样做可以，但我认为您需要发布您的查询，因为可能有更好的解决方案
select upper(substr(<column>,1,1)) || substr(<column>,2,9999) from dual
回答by RAG
To change stringto String, you can use this:
要更改string为String，您可以使用：
SELECT
regexp_replace ('string', '[a-z]', upper (substr ('string', 1, 1)), 1, 1, 'i')
FROM dual;
This assumes that the first letter is the one you want to convert. It your input text starts with a number, such as 2 stringsthen it won't change it to 2 Strings.
这假设第一个字母是您要转换的字母。如果您的输入文本以数字开头，2 strings则不会将其更改为2 Strings.
回答by Daniela
You can also use the column number instead of the name or alias:
您还可以使用列号代替名称或别名：
select distinct p.nr, initcap(p.firstname), initcap(p.lastname), ill.describtion
from patient p left join illness ill
on p.id = ill.id
where p.deleted = 0
order by 3, 2;
