when doing ETL process from cache database to mysql database(ods) and to another mysql database(dwd).

There are lots of DR columns in one table.

In the first step we need two databases to be totally consistent(ods=cache database)

However, the DR column in another database lost its meaning and become to normal number.

In the last step we do the data governance in ODS to DWD. My question is how to write sql without many `join` in this step.

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