Warning: file_get_contents(/data/phpspider/zhask/data//catemap/4/postgresql/9.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
PostgreSQL子串提取_Postgresql_Substring - Fatal编程技术网

PostgreSQL子串提取

PostgreSQL子串提取,postgresql,substring,Postgresql,Substring,我有一个名为“uri”的列,其值如下: file://c:\file1.txt file://\\1.1.1.1\folder1\folder1a\file2.txt file://d:\sub1\sub2\sub3\file3.txt 我正在尝试从uri中删除文件名以离开 file://c:\ file://\\1.1.1.1\folder1\folder1a\ file://d:\sub1\sub2\sub3\ 您可以使用regexp\u replace: with t (col) as

我有一个名为“uri”的列,其值如下:

file://c:\file1.txt
file://\\1.1.1.1\folder1\folder1a\file2.txt
file://d:\sub1\sub2\sub3\file3.txt
我正在尝试从uri中删除文件名以离开

file://c:\
file://\\1.1.1.1\folder1\folder1a\
file://d:\sub1\sub2\sub3\

您可以使用
regexp\u replace

with t (col) as (
    select 'file://c:\file1.txt' union all
    select 'file://\\1.1.1.1\folder1\folder1a\file2.txt' union all
    select 'file://d:\sub1\sub2\sub3\file3.txt'
)
select regexp_replace(col, '(^.*?)[^\\]*$', '\1') as output from t;
产生:

output
---------------------------------
file://c:\
file://\\1.1.1.1\folder1\folder1a\
file://d:\sub1\sub2\sub3\

你已经试过什么了?看看这个。regexp\u replace(您的列名称“^.+[/\]”,“”)