Package org.apache.flink.table.planner.utils

Class Expander

java.lang.Object

org.apache.flink.table.planner.utils.Expander

public class Expander
extends Object

Utility that expand SQL identifiers in a SQL query.

Simple use:

final String sql =
"select ename from emp where deptno < 10";
final Expander.Expanded expanded =
Expander.create(planner).expanded(sql);
print(expanded); // "select `emp`.`ename` from `catalog`.`db`.`emp` where `emp`.`deptno` < 10"

Calling Expander.Expanded.toString() generates a string that is similar to SQL where a user has manually converted all identifiers as expanded, and which could then be persisted as expanded query of a Catalog view.

For more advanced formatting, use Expander.Expanded.substitute(Function).

Adjust SqlParser.Config to use a different parser or parsing options.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Expander.Expanded	Result of expanding.

Method Summary

Modifier and Type	Method	Description
static Expander	create(FlinkPlannerImpl planner)	Creates an Expander
Expander.Expanded	expanded(String ori)	Expands identifiers in a given SQL string, returning a Expander.Expanded.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

create

public static Expander create(FlinkPlannerImpl planner)

Creates an Expander. *

expanded

public Expander.Expanded expanded(String ori)

Expands identifiers in a given SQL string, returning a Expander.Expanded.