Package gudusoft.gsqlparser.nodes

Class TResultColumn

Object

gudusoft.gsqlparser.nodes.TParseTreeNode

gudusoft.gsqlparser.nodes.TNodeWithAliasClause

gudusoft.gsqlparser.nodes.TResultColumn

All Implemented Interfaces:

Visitable, Comparable, Iterator<TSourceToken>

public class TResultColumn
extends TNodeWithAliasClause
implements Comparable

This class represents select_list item in select statement, lets you specify the columns you want to retrieve from the table.

Syntax:

 query_name|[schema.]{table|view|materialized_view}|expr [ [AS] alias]

or, set column values in update_set_clause.

Syntax:

column = expr|(subquery)

or, values clause in insert statement was represented by TResultColumnList.

Syntax:

(expr,expr) 

Field Summary

Fields inherited from class gudusoft.gsqlparser.nodes.TParseTreeNode

dbvendor, doubleLinkedTokenListToString, nodeActionAppend, nodeActionInsert, nodeActionRemove, nodeActionUnknown, nodeActionUpdate, nodeActionUpdateText, nodeChangeEndToken, nodeChangeStartToken

Constructor Summary

Constructors

Constructor	Description
TResultColumn()

Method Summary

Modifier and Type	Method	Description
void	accept(TParseTreeVisitor v)	Accept a visitor
void	acceptChildren(TParseTreeVisitor v)	Accept a visitor to iterate this class and sub-nodes of this class
int	compareTo(Object o)
void	doParse(TCustomSqlStatement psql, ESqlClause plocation)	Analyze the sub-nodes inside this node.
String	getAliasName()
ArrayList<TObjectName>	getAliasNameList()
ArrayList<TObjectName>	getAttributesFromUpLevelReferenceToStarColumn()	这个属性只对 star column 有效。用来存放在 up level 中找到的关联到本 star column 的 column， 主要用来把来自 up level 的这些 column 继续和 本层 from clause 中的 table 关联起来， 以解决 up level column 来自低层哪个 table 的问题 实现代码见：TStarColumnPushDownResolver.preVisit(TSelectSqlStatement stmt)， TAttributeNode.addAttributeRefToThisNode(TObjectName objectName)
String	getColumnAlias()
TObjectName	getColumnFullname()
String	getColumnNameOnly()
String	getDisplayName()	This is the display name shown in the output of select list
TObjectNameList	getExceptColumnList()	Bigquery except columns SELECT COMMON.* EXCEPT (column1, column2) FROM dataset1.table1 COMMON;
TExpression	getExpr()	column expression.
ArrayList<TReplaceExprAsIdentifier>	getExprAsIdentifiers()	BigQuery replace columns SELECT * REPLACE (quantity/2 AS quantity)
TObjectName	getFieldAttr()
String	getPrefixDatabase()
String	getPrefixSchema()
String	getPrefixServer()
String	getPrefixTable()
TQualifyClause	getQualifyClause()
ArrayList<TReplaceExprAsIdentifier>	getReplaceExprAsIdentifiers()	BigQuery select * except(expr as identifier)
TObjectNameList	getTargetColumns()
TUpdateFor	getUpdateFor()
void	init(Object arg1)	Initialize a query tree node.
void	init(Object arg1, Object arg2)
boolean	isMatchedUsingAlias(TObjectName pColumn)
boolean	isMatchedWithResultColumn(EDbVendor dbVendor, TObjectName pColumn)
boolean	isPlaceHolder()	this is true when there is no column names specified for fields in teradata insert statement
void	setAliasName(String aliasName)
void	setDataTypeConversionList(TPTNodeList<TExplicitDataTypeConversion> dataTypeConversionList)
void	setExpr(TExpression expr)
void	setPlaceHolder(boolean placeHolder)
void	setQualifyClause(TQualifyClause qualifyClause)
void	setTargetColumns(TObjectNameList targetColumns)
void	setUpdateFor(TUpdateFor updateFor)
void	TResultColumn()

Methods inherited from class gudusoft.gsqlparser.nodes.TNodeWithAliasClause

getAliasClause, setAliasClause, toString

Methods inherited from class gudusoft.gsqlparser.nodes.TParseTreeNode

addAllMyTokensToTokenList, addToTokenChain, appendNewNode, calculateTokenCount, doAppendNewNode, fastSetString, getAnchorNode, getColumnNo, getCommentAfterNode, getCommentBeforeNode, getCompactString, getDummyTag, getEndToken, getEvaluateDatatype, getEvalValue, getGsqlparser, getLineNo, getLocation, getMd5, getNodeStatus, getNodeType, getParentObjectName, getPlainText, getStartToken, getTokenCount, hasNext, init, init, init, init, insertAfterAToken, insertNewNodeBeforeMe, isChanged, isTokensInChain, next, refreshAllNodesTokenCount, remove, removeAllMyTokensFromTokenList, removeTokens, removeTokensBetweenNodes, removeTokensBetweenToken, replaceWithNewNode, resetIterator, setAnchorNode, setChanged, setDummyTag, setEndToken, setEndToken, setEndToken, setEndToken, setEndToken, setEndTokenDirectly, setEvaluateDatatype, setEvalValue, setGsqlparser, setIncludingComment, setLocation, setNewSubNode, setNodeStatus, setNodeType, setParent, setPlainText, setStartToken, setStartToken, setStartToken, setStartToken, setStartTokenDirectly, setString, setString2, subNodeInNode, toScript, toString2

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Details

TResultColumn

public TResultColumn()

Method Details

getAliasNameList

public ArrayList<TObjectName> getAliasNameList()

getAttributesFromUpLevelReferenceToStarColumn

public ArrayList<TObjectName> getAttributesFromUpLevelReferenceToStarColumn()

这个属性只对 star column 有效。用来存放在 up level 中找到的关联到本 star column 的 column， 主要用来把来自 up level 的这些 column 继续和 本层 from clause 中的 table 关联起来， 以解决 up level column 来自低层哪个 table 的问题 实现代码见：TStarColumnPushDownResolver.preVisit(TSelectSqlStatement stmt)， TAttributeNode.addAttributeRefToThisNode(TObjectName objectName)

Returns:

setAliasName

public void setAliasName(String aliasName)

getAliasName

public String getAliasName()

getExprAsIdentifiers

public ArrayList<TReplaceExprAsIdentifier> getExprAsIdentifiers()

BigQuery replace columns
SELECT * REPLACE (quantity/2 AS quantity)

Returns:

replace expr as identifier list

getExceptColumnList

public TObjectNameList getExceptColumnList()

Bigquery except columns SELECT COMMON.* EXCEPT (column1, column2) FROM dataset1.table1 COMMON;

Returns:

Bigquery except columns

getReplaceExprAsIdentifiers

public ArrayList<TReplaceExprAsIdentifier> getReplaceExprAsIdentifiers()

BigQuery select * except(expr as identifier)

Returns:

setQualifyClause

public void setQualifyClause(TQualifyClause qualifyClause)

getQualifyClause

public TQualifyClause getQualifyClause()

setDataTypeConversionList

public void setDataTypeConversionList(TPTNodeList<TExplicitDataTypeConversion> dataTypeConversionList)

getTargetColumns

public TObjectNameList getTargetColumns()

isMatchedUsingAlias

public boolean isMatchedUsingAlias(TObjectName pColumn)

isMatchedWithResultColumn

public boolean isMatchedWithResultColumn(EDbVendor dbVendor,
 TObjectName pColumn)

TResultColumn

public void TResultColumn()

getDisplayName

public String getDisplayName()

This is the display name shown in the output of select list

Returns:

display name

getColumnAlias

public String getColumnAlias()

getColumnFullname

public TObjectName getColumnFullname()

getColumnNameOnly

public String getColumnNameOnly()

setExpr

public void setExpr(TExpression expr)

setPlaceHolder

public void setPlaceHolder(boolean placeHolder)

isPlaceHolder

public boolean isPlaceHolder()

this is true when there is no column names specified for fields in teradata insert statement

INSERT INTO employee (10005, 'Orebo B',300,,,, 'Nov 17 1957','M',,,18,);

Returns:

getExpr

public TExpression getExpr()

column expression. If there is only column name in a select_list item, then, this expr is type of TExpression.simpleObjectname,

Otherwise, it maybe a complex expr, you should check TExpression.getExpressionType().

for column values in update_set_clause, this expr is type of TExpression.ASSIGNMENT

Returns:

init

public void init(Object arg1)

Description copied from class: TParseTreeNode

Initialize a query tree node. Used internally

Overrides:

init in class TParseTreeNode

Parameters:

arg1 - first argument

init

public void init(Object arg1,
 Object arg2)

Overrides:

init in class TParseTreeNode

doParse

public void doParse(TCustomSqlStatement psql,
 ESqlClause plocation)

Description copied from class: TParseTreeNode

Analyze the sub-nodes inside this node. Such as build the relationship between table and column.

Overrides:

doParse in class TParseTreeNode

Parameters:

psql - SQL statement this node belongs to

plocation - SQL clause this node belongs to

getFieldAttr

public TObjectName getFieldAttr()

Returns:

this is used to provide back compatibility of .NET version only.

getPrefixTable

public String getPrefixTable()

getPrefixSchema

public String getPrefixSchema()

getPrefixDatabase

public String getPrefixDatabase()

getPrefixServer

public String getPrefixServer()

accept

public void accept(TParseTreeVisitor v)

Description copied from class: TParseTreeNode

Accept a visitor

Specified by:

accept in interface Visitable

Overrides:

accept in class TParseTreeNode

Parameters:

v - visitor is a descendant class of TParseTreeVisitor

acceptChildren

public void acceptChildren(TParseTreeVisitor v)

Description copied from class: TParseTreeNode

Accept a visitor to iterate this class and sub-nodes of this class

Specified by:

acceptChildren in interface Visitable

Overrides:

acceptChildren in class TParseTreeNode

Parameters:

v - visitor is a descendant class of TParseTreeVisitor

setTargetColumns

public void setTargetColumns(TObjectNameList targetColumns)

setUpdateFor

public void setUpdateFor(TUpdateFor updateFor)

getUpdateFor

public TUpdateFor getUpdateFor()

compareTo

public int compareTo(Object o)

Specified by:

compareTo in interface Comparable