Package org.apache.drill.exec.planner.sql.handlers

Class ShowTablesHandler

java.lang.Object

org.apache.drill.exec.planner.sql.handlers.AbstractSqlHandler

org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler

org.apache.drill.exec.planner.sql.handlers.ShowTablesHandler

public class ShowTablesHandler
extends DefaultSqlHandler

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler

DefaultSqlHandler.ConvertedRelNode, DefaultSqlHandler.MetaDataProviderModifier

Field Summary

Fields inherited from class org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler

config, context

Constructor Summary

Constructors

Constructor	Description
ShowTablesHandler(SqlHandlerConfig config)

Method Summary

Modifier and Type	Method	Description
org.apache.calcite.sql.SqlNode	rewrite(org.apache.calcite.sql.SqlNode sqlNode)	Rewrite the parse tree as SELECT ...
protected DefaultSqlHandler.ConvertedRelNode	validateAndConvert(org.apache.calcite.sql.SqlNode sqlNode)	Rewritten SHOW TABLES query should be executed against root schema.

Methods inherited from class org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler

addRenamedProject, convertToDrel, convertToPlan, convertToPop, convertToPrel, convertToRawDrel, getPlan, getPops, log, log, log, logAndSetTextPlan, transform, transform, validateNode

Methods inherited from class org.apache.drill.exec.planner.sql.handlers.AbstractSqlHandler

unwrap

Methods inherited from class java.lang.Object

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

Constructor Details

ShowTablesHandler

public ShowTablesHandler(SqlHandlerConfig config)

Method Details

rewrite

public org.apache.calcite.sql.SqlNode rewrite(org.apache.calcite.sql.SqlNode sqlNode)
                                       throws ForemanSetupException

Rewrite the parse tree as SELECT ... FROM INFORMATION_SCHEMA.`TABLES` ...

Overrides:

rewrite in class DefaultSqlHandler

Parameters:

sqlNode - sql parse tree to be rewritten

Returns:

Rewritten sql parse tree

Throws:

ForemanSetupException

validateAndConvert

protected DefaultSqlHandler.ConvertedRelNode validateAndConvert(org.apache.calcite.sql.SqlNode sqlNode)
                                                         throws ForemanSetupException,
org.apache.calcite.tools.RelConversionException,
org.apache.calcite.tools.ValidationException

Rewritten SHOW TABLES query should be executed against root schema. Otherwise if query executed against, for example, jdbc plugin, returned table_schema column values won't be consistent with Drill's values for same column. Also after jdbc filter push down schema condition will be broken because it may contain name of Drill's storage plugin or name of jdbc catalog which isn't present in table_schema column.

Overrides:

validateAndConvert in class DefaultSqlHandler

Parameters:

sqlNode - node produced by rewrite(SqlNode)

Returns:

converted rel node

Throws:

ForemanSetupException - when fragment setup or ser/de failed

org.apache.calcite.tools.RelConversionException - when conversion failed

org.apache.calcite.tools.ValidationException - when sql node validation failed