edu.yale.cs.hadoopdb.sms
Class SQLQueryGenerator

java.lang.Object
  edu.yale.cs.hadoopdb.sms.SQLQueryGenerator

public class SQLQueryGenerator
extends java.lang.Object

Performs Hive plan analysis and builds relevant SQL queries

Field Summary

private static java.lang.String	HIVE_COLUMN_PREFIX
static org.apache.commons.logging.Log	LOG

Constructor Summary

SQLQueryGenerator()

Method Summary

private static java.lang.String	buildSQLQuery(SQLQuery sqlStructure, java.lang.String alias, org.apache.hadoop.hive.ql.metadata.Table tbl, java.lang.StringBuilder sqlWhere, java.lang.StringBuilder sqlGroupBy) Builds actual SQL query to execute against DBMS
private static java.lang.String	funcSQL(java.util.HashMap<java.lang.String,java.lang.String> columnsMapping, org.apache.hadoop.hive.ql.plan.exprNodeFuncDesc func) Handles predicates including nested ones
private static void	generateDefaultSchema(SQLQuery sqlStructure, org.apache.hadoop.hive.ql.metadata.Table tbl) Generates default table schema (as in table definition)
private static java.lang.String	getAlias(java.util.Map<java.lang.String,org.apache.hadoop.hive.ql.plan.exprNodeDesc> map, org.apache.hadoop.hive.ql.plan.exprNodeDesc expr) Returns alias for Hive expression as specified in the column renaming map
private static java.lang.String	getColumnFromExpr(org.apache.hadoop.hive.ql.plan.exprNodeDesc expr, java.util.HashMap<java.lang.String,java.lang.String> columnsMapping) Takes the first column from expression
static void	hackMapredWorkSchema(SQLQuery sqlStructure, org.apache.hadoop.hive.ql.metadata.Table tbl) Cheats Hive's internal table schema with that to be returned by DBMS
private static java.lang.String	prefixColumnIndex(int i) Returns internal column id with prefix
static void	process(org.apache.hadoop.hive.conf.HiveConf conf, org.apache.hadoop.hive.ql.parse.QB qb, java.util.HashMap<java.lang.String,org.apache.hadoop.hive.ql.exec.Operator<? extends java.io.Serializable>> topOps) Performs Hive's plan analysis and SQL generation for all tables
private static void	processFilter(org.apache.hadoop.hive.ql.exec.FilterOperator op, SQLQuery sqlStructure, java.util.HashMap<java.lang.String,java.lang.String> columnsMapping, java.lang.StringBuilder sqlWhere) Handles FilterOperator
private static void	processGroupBy(org.apache.hadoop.hive.ql.exec.GroupByOperator op, SQLQuery sqlStructure, java.util.HashMap<java.lang.String,java.lang.String> columnsMapping, java.util.Map<java.lang.String,org.apache.hadoop.hive.ql.plan.exprNodeDesc> exprAliasMap, java.lang.StringBuilder sqlGroupBy) Handles GroupByOperator
private static void	processSelect(org.apache.hadoop.hive.ql.exec.SelectOperator op, SQLQuery sqlStructure, java.util.HashMap<java.lang.String,java.lang.String> columnsMapping, java.util.Map<java.lang.String,org.apache.hadoop.hive.ql.plan.exprNodeDesc> exprAliasMap) Handles SelectOperator
static SQLQuery	processTable(java.lang.String alias, org.apache.hadoop.hive.ql.metadata.Table tbl, org.apache.hadoop.hive.ql.exec.TableScanOperator tableScanOp) Builds SQL query for a given Hive's table
private static void	removeOperator(org.apache.hadoop.hive.ql.exec.Operator op) Removes operators from Hive's plan

Methods inherited from class java.lang.Object

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

Field Detail

HIVE_COLUMN_PREFIX

private static final java.lang.String HIVE_COLUMN_PREFIX

See Also:

Constant Field Values

LOG

public static final org.apache.commons.logging.Log LOG

Constructor Detail

SQLQueryGenerator

public SQLQueryGenerator()

Method Detail

buildSQLQuery

private static java.lang.String buildSQLQuery(SQLQuery sqlStructure,
                                              java.lang.String alias,
                                              org.apache.hadoop.hive.ql.metadata.Table tbl,
                                              java.lang.StringBuilder sqlWhere,
                                              java.lang.StringBuilder sqlGroupBy)

Builds actual SQL query to execute against DBMS

funcSQL

private static java.lang.String funcSQL(java.util.HashMap<java.lang.String,java.lang.String> columnsMapping,
                                        org.apache.hadoop.hive.ql.plan.exprNodeFuncDesc func)

Handles predicates including nested ones

generateDefaultSchema

private static void generateDefaultSchema(SQLQuery sqlStructure,
                                          org.apache.hadoop.hive.ql.metadata.Table tbl)

Generates default table schema (as in table definition)

getAlias

private static java.lang.String getAlias(java.util.Map<java.lang.String,org.apache.hadoop.hive.ql.plan.exprNodeDesc> map,
                                         org.apache.hadoop.hive.ql.plan.exprNodeDesc expr)

Returns alias for Hive expression as specified in the column renaming map

getColumnFromExpr

private static java.lang.String getColumnFromExpr(org.apache.hadoop.hive.ql.plan.exprNodeDesc expr,
                                                  java.util.HashMap<java.lang.String,java.lang.String> columnsMapping)

Takes the first column from expression

hackMapredWorkSchema

public static void hackMapredWorkSchema(SQLQuery sqlStructure,
                                        org.apache.hadoop.hive.ql.metadata.Table tbl)

Cheats Hive's internal table schema with that to be returned by DBMS

prefixColumnIndex

private static java.lang.String prefixColumnIndex(int i)

Returns internal column id with prefix

process

public static void process(org.apache.hadoop.hive.conf.HiveConf conf,
                           org.apache.hadoop.hive.ql.parse.QB qb,
                           java.util.HashMap<java.lang.String,org.apache.hadoop.hive.ql.exec.Operator<? extends java.io.Serializable>> topOps)

Performs Hive's plan analysis and SQL generation for all tables

processFilter

private static void processFilter(org.apache.hadoop.hive.ql.exec.FilterOperator op,
                                  SQLQuery sqlStructure,
                                  java.util.HashMap<java.lang.String,java.lang.String> columnsMapping,
                                  java.lang.StringBuilder sqlWhere)

Handles FilterOperator

processGroupBy

private static void processGroupBy(org.apache.hadoop.hive.ql.exec.GroupByOperator op,
                                   SQLQuery sqlStructure,
                                   java.util.HashMap<java.lang.String,java.lang.String> columnsMapping,
                                   java.util.Map<java.lang.String,org.apache.hadoop.hive.ql.plan.exprNodeDesc> exprAliasMap,
                                   java.lang.StringBuilder sqlGroupBy)

Handles GroupByOperator

processSelect

private static void processSelect(org.apache.hadoop.hive.ql.exec.SelectOperator op,
                                  SQLQuery sqlStructure,
                                  java.util.HashMap<java.lang.String,java.lang.String> columnsMapping,
                                  java.util.Map<java.lang.String,org.apache.hadoop.hive.ql.plan.exprNodeDesc> exprAliasMap)

Handles SelectOperator

processTable

public static SQLQuery processTable(java.lang.String alias,
                                    org.apache.hadoop.hive.ql.metadata.Table tbl,
                                    org.apache.hadoop.hive.ql.exec.TableScanOperator tableScanOp)

Builds SQL query for a given Hive's table

removeOperator

private static void removeOperator(org.apache.hadoop.hive.ql.exec.Operator op)

Removes operators from Hive's plan