org.apache.lens.driver.jdbc

Class ColumnarSQLRewriter

java.lang.Object

org.apache.lens.driver.jdbc.ColumnarSQLRewriter

All Implemented Interfaces:

QueryRewriter

public class ColumnarSQLRewriter
extends Object
implements QueryRewriter

The Class ColumnarSQLRewriter.

Constructor Summary

Constructors

Constructor and Description
ColumnarSQLRewriter() Instantiates a new columnar sql rewriter.

Method Summary

Methods

Modifier and Type	Method and Description
void	analyzeInternal(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.hive.conf.HiveConf hconf) Analyze internal.
void	buildQuery(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.hive.conf.HiveConf hconf) Builds the query.
void	buildSubqueries(org.apache.hadoop.hive.ql.parse.ASTNode node) Builds the subqueries.
StringBuilder	constructJoinChain() Construct join chain
void	factFilterPushDown(org.apache.hadoop.hive.ql.parse.ASTNode node) Get fact filters for pushdown
ArrayList<String>	getAggregateColumns(org.apache.hadoop.hive.ql.parse.ASTNode node) Gets the aggregate columns.
void	getAllFactKeys() Get all fact keys used in all ASTs
void	getAllFilters(org.apache.hadoop.hive.ql.parse.ASTNode node) Gets the all filters.
String	getClause()
int	getColumnCount(org.apache.hadoop.hive.ql.parse.ASTNode node) Get the count of columns in a given select expression
String	getFactAlias() Get the fact alias
void	getFactKeysFromNode(org.apache.hadoop.hive.ql.parse.ASTNode node) Get fact keys used in the AST
String	getFactNameAlias(org.apache.hadoop.hive.ql.parse.ASTNode fromAST) Gets the fact name alias.
void	getFilterInJoinCond(org.apache.hadoop.hive.ql.parse.ASTNode node) Gets the filter in join cond.
void	getJoinCond(org.apache.hadoop.hive.ql.parse.ASTNode node) Gets the join cond.
String	getLimitClause(org.apache.hadoop.hive.ql.parse.ASTNode node) Gets the limit clause.
String	getTableFromTabRefNode(org.apache.hadoop.hive.ql.parse.ASTNode tree) Gets the table from tab ref node.
String	getTableOrAlias(String keyString, String type) Get the table or alias from the given key string
ArrayList<String>	getTablesAndColumns(org.apache.hadoop.hive.ql.parse.ASTNode node) Gets the tables and columns.
void	init(org.apache.hadoop.conf.Configuration conf) Set conf for the rewriter
boolean	isExpressionsUsed(org.apache.hadoop.hive.ql.parse.ASTNode node) Check if expression is used in select
void	replaceAliasInAST() Replace alias in AST trees
String	replaceUDFForDB(String query) Replace udf for db.
void	reset() Reset.
String	rewrite(String query, org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.hive.conf.HiveConf metastoreConf) Rewrite.

Methods inherited from class java.lang.Object

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

Constructor Detail

ColumnarSQLRewriter

public ColumnarSQLRewriter()

Instantiates a new columnar sql rewriter.

Method Detail

init

public void init(org.apache.hadoop.conf.Configuration conf)

Description copied from interface: QueryRewriter

Set conf for the rewriter

Specified by:

init in interface QueryRewriter

Parameters:

conf - Configuration required for rewriter init

getClause

public String getClause()

analyzeInternal

public void analyzeInternal(org.apache.hadoop.conf.Configuration conf,
                   org.apache.hadoop.hive.conf.HiveConf hconf)
                     throws org.apache.hadoop.hive.ql.parse.SemanticException

Analyze internal.

Throws:

org.apache.hadoop.hive.ql.parse.SemanticException - the semantic exception

getTableFromTabRefNode

public String getTableFromTabRefNode(org.apache.hadoop.hive.ql.parse.ASTNode tree)

Gets the table from tab ref node.

Parameters:

tree - the tree

Returns:

the table from tab ref node

getJoinCond

public void getJoinCond(org.apache.hadoop.hive.ql.parse.ASTNode node)

Gets the join cond.

Parameters:

node - the node

constructJoinChain

public StringBuilder constructJoinChain()

Construct join chain

Returns:

getColumnCount

public int getColumnCount(org.apache.hadoop.hive.ql.parse.ASTNode node)

Get the count of columns in a given select expression

Parameters:

node -

Returns:

Column count

isExpressionsUsed

public boolean isExpressionsUsed(org.apache.hadoop.hive.ql.parse.ASTNode node)

Check if expression is used in select

Parameters:

node -

Returns:

true if expressions is used

getFilterInJoinCond

public void getFilterInJoinCond(org.apache.hadoop.hive.ql.parse.ASTNode node)

Gets the filter in join cond.

Parameters:

node - the node

getFactAlias

public String getFactAlias()

Get the fact alias

Returns:

factFilterPushDown

public void factFilterPushDown(org.apache.hadoop.hive.ql.parse.ASTNode node)

Get fact filters for pushdown

Parameters:

node -

getFactKeysFromNode

public void getFactKeysFromNode(org.apache.hadoop.hive.ql.parse.ASTNode node)

Get fact keys used in the AST

Parameters:

node -

getAllFactKeys

public void getAllFactKeys()

Get all fact keys used in all ASTs

buildSubqueries

public void buildSubqueries(org.apache.hadoop.hive.ql.parse.ASTNode node)

Builds the subqueries.

Parameters:

node - the node

getTableOrAlias

public String getTableOrAlias(String keyString,
                     String type)

Get the table or alias from the given key string

Parameters:

keyString -

type -

Returns:

getAggregateColumns

public ArrayList<String> getAggregateColumns(org.apache.hadoop.hive.ql.parse.ASTNode node)

Gets the aggregate columns.

Parameters:

node - the node

Returns:

the aggregate columns

getTablesAndColumns

public ArrayList<String> getTablesAndColumns(org.apache.hadoop.hive.ql.parse.ASTNode node)

Gets the tables and columns.

Parameters:

node - the node

Returns:

the tables and columns

getLimitClause

public String getLimitClause(org.apache.hadoop.hive.ql.parse.ASTNode node)

Gets the limit clause.

Parameters:

node - the node

Returns:

the limit clause

getAllFilters

public void getAllFilters(org.apache.hadoop.hive.ql.parse.ASTNode node)

Gets the all filters.

Parameters:

node - the node

getFactNameAlias

public String getFactNameAlias(org.apache.hadoop.hive.ql.parse.ASTNode fromAST)

Gets the fact name alias.

Parameters:

fromAST - the from ast

Returns:

the fact name alias

reset

public void reset()

Reset.

replaceUDFForDB

public String replaceUDFForDB(String query)

Replace udf for db.

Parameters:

query - the query

Returns:

the string

replaceAliasInAST

public void replaceAliasInAST()

Replace alias in AST trees

buildQuery

public void buildQuery(org.apache.hadoop.conf.Configuration conf,
              org.apache.hadoop.hive.conf.HiveConf hconf)
                throws org.apache.hadoop.hive.ql.parse.SemanticException

Builds the query.

Throws:

org.apache.hadoop.hive.ql.parse.SemanticException

rewrite

public String rewrite(String query,
             org.apache.hadoop.conf.Configuration conf,
             org.apache.hadoop.hive.conf.HiveConf metastoreConf)
               throws LensException

Description copied from interface: QueryRewriter

Rewrite.

Specified by:

rewrite in interface QueryRewriter

Parameters:

query - the query

conf - the query configuration

metastoreConf - The metastore configuration. If rewriters requires to access metastore, this configuration needs to passed

Returns:

the string

Throws:

LensException - the lens exception