mysql - #1062 - key '' 的重复条目 'primary'

Question

Table 1 - leads
column 1 - lead_source_description

Table 2 - leads_cstm
column 2 -referrer_c 

我尝试使用以下查询将值从 table2.column2 复制到 table1.column1

INSERT INTO leads (`lead_source_description`)
SELECT `referrer__c`
FROM leads_cstm

我知道这是一项简单的任务，并且已经被要求了。但我收到以下错误。

#1062 - Duplicate entry '' for key 'PRIMARY'

Answer 1

INSERT INTO leads (`lead_source_description`)
SELECT DISTINCT `referrer__c` FROM leads_cstm