Oracle INSTR 在 Oracle SQL 中落后

Question

我正在尝试在 oracle SQL 中找到一种方法，将第一个“/”之后的所有文本从右边移到第四个“/”。我需要在一个 SQL 语句中执行此操作..

table name: access_log
col name: download
value: Download file:/webdocs/data/groupXXX/case/03_28_54_9_0000011856.pdf

我正在尝试结束

case

然后数一数有多少匹配？这个可以吗？

Answer 1

简单的SUBSTR 方法适用于 Oracle 10g+

select TRIM(BOTH '/' FROM 
          substr(
                  download,
                  INSTR(download,'/',1,4),
                  INSTR(download,'/',1,5)-INSTR(download,'/',1,4)
                 )
           )
FROM ACCESS_LOG;

计数可能是，

SELECT
COUNT(
         CASE WHEN TRIM(BOTH '/' FROM 
                        substr(
                                download,
                                INSTR(download,'/',1,4),
                                INSTR(download,'/',1,5)-INSTR(download,'/',1,4)
                               )
                         ) = 'case'
         THEN
             1
         END
       ) COUNT_MATCHED
FROM 
     ACCESS_LOG;

Answer 2

select regexp_replace('Download file:/webdocs/data/groupXXX/case/03_28_54_9_0000011856.pdf', 
                      '.*/([^/]+)/[^/]*$', '\1') from dual;