initcap 仅适用于超过三个字符的单词答案

【问题标题】：initcap only for words with more than three characterinitcap 仅适用于超过三个字符的单词
【发布时间】：2019-09-16 18:06:27
【问题描述】：

我正在尝试创建一个将 initcap 应用于字段的选择语句，但我想只将超过三个字符的单词设为大写。

请注意，我无法创建外部函数，并且我的问题没有通过这个答案解决： Initcap skip words smaller than 4 characters

因为他们解决了使用手动检查匹配项的过程。

所以我想使用一些东西：

SELECT REGEXP_REPLACE(initcap(myField),"\w{1,10}\b") FROM dual

MyField 包含类似 GUNS N ROSES 的内容，我想转变成 Guns n Roses

【问题讨论】：

REGEXP_REPLACE() 需要 3 个参数：列名、正则表达式和替换字符串。

标签： sql regex oracle

【解决方案1】：

你需要为它执行单独的逻辑。

如果length超过3个字符，则需要将语句分解为单个单词并执行initcap。之后使用aggregate function 将它们组合起来。

WITH DATAA AS
(SELECT 'GUNS N ROSES' AS STR FROM DUAL)

SELECT LISTAGG(CASE WHEN LENGTH(STRR) > 3       
                    THEN INITCAP(STRR) 
                    ELSE STRR 
               END, ' ')
       WITHIN GROUP (ORDER BY LVL) AS RESULT
FROM
  (SELECT LEVEL AS LVL, 
          LOWER(REGEXP_SUBSTR(STR, '[^ ]+', 1, LEVEL)) AS STRR
     FROM DATAA
   CONNECT BY LEVEL <= REGEXP_COUNT(STR, ' ') + 1);

db<>fiddle demo

干杯！！

【讨论】：

干得好，但您在示例末尾缺少一个紧跟括号。

【解决方案2】：

与 Tejash 的回答类似，但有一些额外的逻辑可以在多行上执行 CONNECT BY。

-- example data
with mytable as (select 'GUNS N ROSES' as myfield from dual
            union select 'SALPHEN AAN DEN RIJN' from dual
            union select 'KAAG EN BRAASSEM' from dual)
-- query
select listagg(CASE WHEN length(words.word) > 3 
                    THEN initcap(words.word) 
                    ELSE lower(words.word) 
               END, ' ') within group (order by words.lvl)
from 
  (select myfield, regexp_substr(myfield,'\w+', 1, level) as word, level as lvl
    from mytable
    connect by regexp_substr(myfield, '\w+', 1, level) is not null
      and PRIOR myfield = myfield
      and PRIOR SYS_GUID() is not null) words
group by words.myfield  
;

【讨论】：

【解决方案3】：

逐字替换值，无需拆分和重新聚合句子。

Oracle 设置

CREATE TABLE table_name( sentence ) AS
SELECT 'GUNS N ROSES' FROM DUAL UNION ALL
SELECT 'THIS IS A SENTENCE THAT SHOULD BE IN INITCAPS IF IT HAS MORE THAN THREE LETTERS' FROM DUAL UNION ALL
SELECT 'FOUR THREE TWO ONE' FROM DUAL

查询：

WITH replaced ( sentence, startidx, endidx ) AS (
  SELECT LOWER( sentence ),
         1,
         REGEXP_INSTR( sentence, '\W', 1 )
  FROM   table_name
UNION ALL
  SELECT CASE
         WHEN endidx - startidx <= 3
         THEN sentence
         ELSE  SUBSTR( sentence, 1, startidx - 1 )
            || INITCAP( SUBSTR( sentence, startidx, endidx - startidx ) )
            || SUBSTR( sentence, endidx )
         END,
         endidx + 1,
         REGEXP_INSTR( sentence, '\W', endidx + 1 )
  FROM   replaced
  WHERE  endidx > 0
)
SELECT CASE
       WHEN LENGTH( sentence ) - startidx <= 3
       THEN sentence
       ELSE  SUBSTR( sentence, 1, startidx - 1 )
          || INITCAP( SUBSTR( sentence, startidx ) )
       END AS sentence
FROM   replaced
WHERE  endidx = 0

输出：

|句子 | | :------------------------------------------------ ------------------------------ | |枪与玫瑰 | |四三二一| |如果它有三个以上的字母，这是一个应该在 Initcaps 中的句子 |

db小提琴here

【讨论】：