如何按列去除重复数据（linux）

背景

将oui.csv文件内容导入数据库，将Assignment字段作为主键，
发现该列数据有重复，导入失败，
需要对该文件按指定列进行去重在进行导入。

文件内容如下，展示10行

Registry,Assignment,Organization Name,Organization Address
MA-L,E043DB,Shenzhen ViewAt Technology Co.，Ltd. ,9A，Microprofit，6th Gaoxin South Road， High-Tech Industrial Park， Nanshan， Shenzhen， CHINA. shenzhen guangdong CN 518057 
MA-L,2405F5,Integrated Device Technology (Malaysia) Sdn. Bhd.,Phase 3， Bayan Lepas FIZ Bayan Lepas Penang MY 11900 
MA-L,3CD92B,Hewlett Packard,11445 Compaq Center Drive Houston  US 77070 
MA-L,9C8E99,Hewlett Packard,11445 Compaq Center Drive Houston  US 77070 
MA-L,B499BA,Hewlett Packard,11445 Compaq Center Drive Houston  US 77070 
MA-L,1CC1DE,Hewlett Packard,11445 Compaq Center Drive Houston  US 77070 
MA-L,3C3556,Cognitec Systems GmbH,Großenhainer Str. 101 Dresden Saxony DE 01127 
MA-L,0050BA,D-Link Corporation,2F， NO. 233L-2， PAO-CHIAO RD. TAIPEI  TW 0000 
MA-L,00179A,D-Link Corporation,No. 289， Sinhu 3rd Rd.， Neihu District， Taipei  TW 114