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| |
| # Project status |
| |
| A snapshot of what works today. The library is in early development; the |
| API will change before the first release. |
| |
| ## Query interfaces |
| |
| - [x] SQL: `SessionContext.sql(String)` |
| - [x] DataFrame: `select`, `filter` (other transformations TBD) |
| - [x] DataFusion-Proto `LogicalPlanNode`: `SessionContext.fromProto(byte[])`. |
| The `datafusion-proto` Java classes are generated by the build. |
| |
| ## Data sources |
| |
| - [x] Parquet via `registerParquet` / `readParquet`, with `ParquetReadOptions` |
| - [x] CSV via `registerCsv` / `readCsv`, with `CsvReadOptions` |
| - [ ] JSON, Avro |
| - [ ] Custom catalog and table providers |
| |
| ## Results |
| |
| - [x] `DataFrame.collect(allocator)` — Arrow C Data Interface stream |
| - [x] `DataFrame.count()`, `show()`, `show(int)` |
| - [x] `SessionContext.tableSchema(String)` |
| |
| ## Not yet |
| |
| - [ ] `SessionConfig` / `RuntimeEnv` knobs |
| - [ ] Java UDFs |
| - [ ] `write_*` outputs |
