README

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Steps of row-to-column conversion:

1. Modify the corresponding cluster configuration in conf.

2. Run python convert_row_to_column.py to generate all row storage to column storage commands.

3. If the script runs without any results, it means that there is no row storage table in the cluster, so nothing need to be done.

4. If there is a table in the script that fails to obtain information.

   Please use show create table in the cluster to see the storage_type of the table. If it is row storage, please manually convert it.

5. After the schema change is completed, the old schema needs to be deleted after 10 minutes.

   Please wait for a while to make sure that the data of the old schema has been deleted, and then upgrade. Otherwise, the BE process will exit with an error when it is automatically detected when it starts.

6. Run python convert_row_to_column.py again to verify that there are no rows in the table before upgrading.