Move data from Cloud Object Storage to ClickHouse Cloud
Currently, ClickHouse Cloud only supports Amazon AWS S3 Object Storage.
If you use a Cloud Object Storage as a data lake and wish to import this data into ClickHouse Cloud, or if your current database system is able to directly offload data into a Cloud Object Storage, then you can use one of the table functions - for now, s3 or s3Cluster) - for migrating data stored in Cloud Object Storage into a ClickHouse Cloud table.
If your current database system is not able to directly offload data into a Cloud Object Storage, you could use a third-party ETL/ELT tool or clickhouse-local for moving data from you current database system to Cloud Object Storage, in order to migrate that data in a second step into a ClickHouse Cloud table.
Although this is a two steps process (offload data into a Cloud Object Storage, then load into ClickHouse), the advantage is that this scales to petabytes thanks to a solid ClickHouse Cloud support of highly-parallel reads from Cloud Object Storage. Also you can leverage sophisticated and compressed formats like Parquet.
There is a blog article with concrete code examples showing how you can get data into ClickHouse Cloud using S3.