📄️ External table
StarRocks supports access to other data sources by using external tables. External tables are created based on data tables that are stored in other data sources. StarRocks only stores the metadata of the data tables. You can use external tables to directly query data in other data sources. StarRocks supports the following data sources: MySQL, Elasticsearch, Hive, StarRocks, Apache Iceberg, and Apache Hudi. Currently, you can only write data from another StarRocks cluster into the current StarRocks cluster. You cannot read data from it. For data sources other than StarRocks, you can only read data from these data sources.
📄️ File external table
File external table is a special type of external table. It allows you to directly query Parquet and ORC data files in external storage systems without loading data into StarRocks. In addition, file external tables do not rely on a metastore. In the current version, StarRocks supports the following external storage systems: HDFS, Amazon S3, and S3-compatible storage systems.
📄️ Data Cache
This topic describes the working principles of Data Cache and how to enable Data Cache to improve query performance on external data.