org.apache.hadoop.hive.ql.optimizer.calcite.translator

Class ASTConverter

java.lang.Object

org.apache.hadoop.hive.ql.optimizer.calcite.translator.ASTConverter

public class ASTConverter
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static String	NON_FK_FILTERED
static String	NON_FK_NOT_FILTERED

Method Summary

Modifier and Type	Method and Description
static ASTNode	convert(org.apache.calcite.rel.RelNode relNode, List<org.apache.hadoop.hive.metastore.api.FieldSchema> resultSchema, boolean alignColumns, PlanMapper planMapper)
static ASTNode	emptyPlan(org.apache.calcite.rel.type.RelDataType dataType) This method generates the abstract syntax tree of a query does not return any rows.
ASTNode	getUnionAllAST(ASTNode leftAST, ASTNode rightAST)
static boolean	isFlat(org.apache.calcite.rex.RexCall call)

Methods inherited from class java.lang.Object

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

Field Detail

NON_FK_FILTERED

public static final String NON_FK_FILTERED

See Also:

Constant Field Values

NON_FK_NOT_FILTERED

public static final String NON_FK_NOT_FILTERED

See Also:

Constant Field Values

Method Detail

convert

public static ASTNode convert(org.apache.calcite.rel.RelNode relNode,
                              List<org.apache.hadoop.hive.metastore.api.FieldSchema> resultSchema,
                              boolean alignColumns,
                              PlanMapper planMapper)
                       throws CalciteSemanticException

Throws:

CalciteSemanticException

emptyPlan

public static ASTNode emptyPlan(org.apache.calcite.rel.type.RelDataType dataType)

This method generates the abstract syntax tree of a query does not return any rows. All projected columns are null and the data types are come from the passed RelDataType.

 SELECT NULL alias0 ... NULL aliasn LIMIT 0;
 

Due to a subsequent optimization when converting the plan to TEZ tasks adding a limit 0 enables Hive not submitting the query to TEZ application manager but returns empty result set immediately.

 TOK_QUERY
   TOK_INSERT
      TOK_DESTINATION
         TOK_DIR
            TOK_TMP_FILE
      TOK_SELECT
         TOK_SELEXPR
            TOK_FUNCTION
               TOK_<type>
               TOK_NULL
            alias0
         ...
         TOK_SELEXPR
            TOK_FUNCTION
               TOK_<type>
               TOK_NULL
            aliasn
      TOK_LIMIT
         0
         0
 

Parameters:

dataType - - Schema

Returns:

Root ASTNode of the result plan.

See Also:

QueryProperties.getOuterQueryLimit(), TaskCompiler.compile(ParseContext, List, Set, Set)

getUnionAllAST

public ASTNode getUnionAllAST(ASTNode leftAST,
                              ASTNode rightAST)

isFlat

public static boolean isFlat(org.apache.calcite.rex.RexCall call)