如下
select x.*,count(1) from (
-- select substr(t.attachmentpath,-3,)v from COMM_ATTACHMENT t
select substr(t.attachmentpath,instr(t.attachmentpath,'.',-1)+1) v from COMM_ATTACHMENT t
) x group by v;
数据源举例：
\project\2018\115\57925\zmcl\150_\201812081635054225275.png \project\2018\115\57988\needDel\886_\201812081649105167112.docx \project\2018\115\57993\proj_report_info\1002_\201812101524574068489.pdf
end
标签：project,115,substr,attachmentpath,2018,oracle,文件类型,上传,select From： https://www.cnblogs.com/xh_Blog/p/17334283.html