Awk按第一列分组

我有这样的数据

prdnf001:app_prd_areas_sp2_ux  
prdnf001:app_prd_cx_local_ux  
prdnf001:app_prd_cx_ux  
prdnf001:app_prd_ftt_ux  
prdnf001:app_prd_local_ux 
prdnf001:app_prd_app_ux  
devnf001:app_syt_ds_backup1  
devnf001:app_syt_ds_sybsft1  
devnf001:app_syt_ftt_ux  
devnf001:app_syt_app_ux 
devnf001:app_uat_cx_ux   

我会这样说：

prdnf001
prdnf001:app_prd_areas_sp2_ux  
prdnf001:app_prd_cx_local_ux  
prdnf001:app_prd_cx_ux  
prdnf001:app_prd_ftt_ux  
prdnf001:app_prd_local_ux 
prdnf001:app_prd_app_ux 
devnf001 
devnf001:app_syt_ds_backup1  
devnf001:app_syt_ds_sybsft1  
devnf001:app_syt_ftt_ux  
devnf001:app_syt_app_ux 
devnf001:app_uat_cx_ux   

这是我目前使用的代码。我做错了什么？ 谢谢

输出：

prdnf001
prdnf001:app_prd_areas_sp2_ux DP prdnf001-dr:app_prd_areas_sp2_ux_m Snapmirrored 
prdnf001:app_prd_cx_local_ux DP prdnf001-dr:app_prd_cx_local_ux_m Snapmirrored 
prdnf001:app_prd_cx_ux DP prdnf001-dr:app_prd_cx_ux_m Snapmirrored 
prdnf001:app_prd_ftt_ux DP prdnf001-dr:app_prd_ftt_ux_m Snapmirrored 
prdnf001:app_prd_local_ux DP prdnf001-dr:app_prd_local_ux_m Snapmirrored 
prdnf001:app_prd_app_ux DP prdnf001-dr:app_prd_app_ux_m Snapmirrored 
devnf001
devnf001:app_syt_ds_backup1 DP tstnf001:app_syt_ds_backup1_m Snapmirrored 
devnf001:app_syt_ds_sybsft1 DP tstnf001:app_syt_ds_sybsft1_m Snapmirrored 
devnf001:app_syt_ftt_ux DP tstnf001:app_syt_ftt_ux_m Snapmirrored 
devnf001:app_syt_app_ux DP tstnf001:app_syt_app_ux_m Snapmirrored 
devnf001:app_uat_cx_ux DP tstnf001:app_uat_cx_ux_m Snapmirrored 

---

将代码包装在代码标签中，您将在编辑代码时看到一个按钮

{}

选择示例并单击它。也请在你的帖子中添加你为解决这个问题所做的努力；

awk -F ':' 'saved!=$1{saved=$1; print saved} {print}' file

prdnf001
prdnf001:app_prd_areas_sp2_ux DP prdnf001-dr:app_prd_areas_sp2_ux_m Snapmirrored 
prdnf001:app_prd_cx_local_ux DP prdnf001-dr:app_prd_cx_local_ux_m Snapmirrored 
prdnf001:app_prd_cx_ux DP prdnf001-dr:app_prd_cx_ux_m Snapmirrored 
prdnf001:app_prd_ftt_ux DP prdnf001-dr:app_prd_ftt_ux_m Snapmirrored 
prdnf001:app_prd_local_ux DP prdnf001-dr:app_prd_local_ux_m Snapmirrored 
prdnf001:app_prd_app_ux DP prdnf001-dr:app_prd_app_ux_m Snapmirrored 
devnf001
devnf001:app_syt_ds_backup1 DP tstnf001:app_syt_ds_backup1_m Snapmirrored 
devnf001:app_syt_ds_sybsft1 DP tstnf001:app_syt_ds_sybsft1_m Snapmirrored 
devnf001:app_syt_ftt_ux DP tstnf001:app_syt_ftt_ux_m Snapmirrored 
devnf001:app_syt_app_ux DP tstnf001:app_syt_app_ux_m Snapmirrored 
devnf001:app_uat_cx_ux DP tstnf001:app_uat_cx_ux_m Snapmirrored