Because the partno field is declared unique, repeated upload operations of the same part number merely replace the old index record with a new record.

由于声明了partno字段惟一，因此重复上传同一个部件号将只用新记录替换旧索引记录。

youdao

Because the partno field is declared unique, repeated upload operations of the same part number merely replace the old index record with a new record.

由于声明了partno字段惟一，因此重复上传同一个部件号将只用新记录替换旧索引记录。

youdao