| # Table Planner |
| |
| This module connects Table/SQL API and runtime. It is responsible for translating and optimizing a table program into a Flink pipeline. |
| For user documentation, check the [table documentation](https://nightlies.apache.org/flink/flink-docs-master/docs/dev/table/overview/). |
| |
| This README contains some development info for table planner contributors. |
| |
| ## Immutables for rules |
| |
| Calcite's `@ImmutableBeans.Property` has been removed in Calcite 1.28.0. |
| |
| Since Flink 1.17, planner rules use [Immutables](http://immutables.github.io/) to generate immutable |
| classes for rule configs based on the provided interface. A config should be annotated with `@Value.Immutable`. |
| In case the config is a nested class, the enclosing one should be annotated with `@Value.Enclosing`. |
| |
| Once a new rule config is written and annotated, compile the module to generate the immutable class |
| for that config. Generated code will be placed in `target/generated-sources/annotations`. The config |
| can then be instantiated with the help of the generated immutable class like `Immutable<EnclosingClassName>.<ConfigClassName>`. |
| |
| In case of issues, please double-check if a required generated class is present. |
| As an example have a look at `org.apache.flink.table.planner.plan.rules.logical.EventTimeTemporalJoinRewriteRule`. |
| See also `org.apache.calcite.plan.RelRule` for detailed explanation from Calcite. |
| |
| ## Json Plan unit tests |
| |
| Unit tests verifying the JSON plan changes (e.g. Java tests in `org.apache.flink.table.planner.plan.nodes.exec.stream`) |
| can regenerate all the files setting the environment variable `PLAN_TEST_FORCE_OVERWRITE=true`. |
