TJoinExpr (General SQL Parser Java Library Core 3.0.9.2 API)

Object
- gudusoft.gsqlparser.nodes.TParseTreeNode
- - gudusoft.gsqlparser.nodes.TNodeWithAliasClause
  - - gudusoft.gsqlparser.nodes.TJoinExpr

All Implemented Interfaces:

IRelation, Visitable, Iterator<TSourceToken>
```
public class TJoinExpr
extends TNodeWithAliasClause
implements IRelation
```
Represents a JOIN expression in SQL statements. This class replaces TJoin as of version 2.7.4.0.
A JOIN expression consists of:
- A left table/subquery (getLeftTable())
- A right table/subquery (getRightTable())
- A join type (getJointype()) - e.g. INNER, LEFT, RIGHT, FULL, CROSS
- An optional ON condition (getOnCondition())
- Optional USING columns (getUsingColumns())
For nested joins, the left and right operands can themselves be JOIN expressions, allowing representation of complex join trees. Use getLeftMostJoinExpr() to traverse to the leftmost join in a nested structure.
PostgreSQL-specific: Supports USING clause aliases via getJoin_using_alias().
The class implements IRelation and maintains a list of available attributes from both sides of the join via getAttributes().
Represents join table in parse tree.

Field Summary

Fields
Modifier and Type Field and Description

TExpression onCondition
on condition;

EJoinType original_jontype

TObjectNameList usingColumns
using (column list)
- Fields inherited from class gudusoft.gsqlparser.nodes.TParseTreeNode
  dbvendor, doubleLinkedTokenListToString, nodeActionAppend, nodeActionInsert, nodeActionRemove, nodeActionUnknown, nodeActionUpdate, nodeActionUpdateText, nodeChangeEndToken, nodeChangeStartToken

Fields
Modifier and Type	Field and Description
`TExpression`	`onCondition` on condition;
`EJoinType`	`original_jontype`
`TObjectNameList`	`usingColumns` using (column list)

Constructor Summary

Constructors
Constructor and Description

TJoinExpr()

Constructors
Constructor and Description
`TJoinExpr()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and 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
`ArrayList<TAttributeNode>`	`getAttributes()` 每个 relation 包含的 attributes 当它为 base table 时，这些 attributes 的来源有三种可能 1.
`TAliasClause`	`getJoin_using_alias()` Postgres: USING ( join_column [, ...] ) [ AS join_using_alias ]
`EJoinType`	`getJointype()`
`TJoinExpr`	`getLeftMostJoinExpr()`
`TFromTable`	`getLeftOperand()` This method is used by parser, do not use it in your code.
`TTable`	`getLeftTable()`
`TExpression`	`getMatchCondition()`
`int`	`getNestedParen()`
`TExpression`	`getOnCondition()`
`String`	`getRelationName()`
`TFromTable`	`getRightOperand()` This method is used by parser, do not use it in your code.
`TTable`	`getRightTable()`
`TObjectNameList`	`getUsingColumns()`
`void`	`incNestedParen()`
`void`	`init(Object arg1)` Initialize a query tree node.
`void`	`init(Object arg1, Object arg2)`
`void`	`initAttributes(int roundNo)`
`void`	`setJoinCondition(TDummy pDummy)`
`void`	`setJoinCondition(TExpression onCondition)`
`void`	`setJointype(EJoinType jointype)`
`void`	`setLeftOperand(TFromTable leftOperand)` This method is used by parser, do not use it in your code.
`void`	`setLeftTable(TTable leftTable)`
`void`	`setMatchCondition(TExpression matchCondition)`
`void`	`setNestedParen(int nestedParen)`
`void`	`setOnCondition(TExpression onCondition)`
`void`	`setRightOperand(TFromTable rightOperand)` This method is used by parser, do not use it in your code.
`void`	`setRightTable(TTable rightTable)`
`void`	`setUsingColumns(TObjectNameList usingColumns)`
`int`	`size()`

Methods inherited from class gudusoft.gsqlparser.nodes.TNodeWithAliasClause
getAliasClause, setAliasClause, toString

Methods inherited from class gudusoft.gsqlparser.nodes.TParseTreeNode
addAllMyTokensToTokenList, addToTokenChain, appendNewNode, calculateTokenCount, doAppendNewNode, doParse, 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 Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface Iterator
forEachRemaining

- Field Detail
  - usingColumns
```
public TObjectNameList usingColumns
```
    using (column list)
  - onCondition
```
public TExpression onCondition
```
    on condition;
  - original_jontype
```
public EJoinType original_jontype
```
- Constructor Detail
  - TJoinExpr
```
public TJoinExpr()
```
- Method Detail
  - getJoin_using_alias
```
public TAliasClause getJoin_using_alias()
```
    Postgres: USING ( join_column [, ...] ) [ AS join_using_alias ]
    
    Returns:
  - initAttributes
```
public void initAttributes(int roundNo)
```
  - getAttributes
```
public ArrayList<TAttributeNode> getAttributes()
```
    Description copied from interface: IRelation
    
    每个 relation 包含的 attributes 当它为 base table 时，这些 attributes 的来源有三种可能 1. 来自数据库的 metadata，第一次 resolve 时就可以获取，来自 sqlenv 2. 来自 create table ddl，第一次 resolve 时就可以获取，来自 sqlenv 3. 来自 sql script，第二次 resolve 时，来自relation的 referenceAttribute 属性。第一、二中来源是可靠的来源，attributes应该是完整的，第三种推断自 sql script，attributes很可能是不完整的。
    
    Specified by:
    
    getAttributes in interface IRelation
    
    Returns:
  - getRelationName
```
public String getRelationName()
```
    Specified by:
    
    getRelationName in interface IRelation
  - size
```
public int size()
```
    Specified by:
    
    size in interface IRelation
  - setLeftTable
```
public void setLeftTable(TTable leftTable)
```
  - setRightTable
```
public void setRightTable(TTable rightTable)
```
  - getLeftTable
```
public TTable getLeftTable()
```
  - getRightTable
```
public TTable getRightTable()
```
  - incNestedParen
```
public void incNestedParen()
```
  - getNestedParen
```
public int getNestedParen()
```
  - getUsingColumns
```
public TObjectNameList getUsingColumns()
```
  - getOnCondition
```
public TExpression getOnCondition()
```
  - getJointype
```
public EJoinType getJointype()
```
  - setJointype
```
public void setJointype(EJoinType jointype)
```
  - getLeftOperand
```
public TFromTable getLeftOperand()
```
    This method is used by parser, do not use it in your code. After parsing, you can use getLeftTable() instead.
  - getRightOperand
```
public TFromTable getRightOperand()
```
    This method is used by parser, do not use it in your code. After parsing, you can use getRightTable() instead.
  - setLeftOperand
```
public void setLeftOperand(TFromTable leftOperand)
```
    This method is used by parser, do not use it in your code. After parsing, you can use setLeftTable() instead.
  - setRightOperand
```
public void setRightOperand(TFromTable rightOperand)
```
    This method is used by parser, do not use it in your code. After parsing, you can use setRightTable() instead.
  - 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
  - setJoinCondition
```
public void setJoinCondition(TDummy pDummy)
```
  - setJoinCondition
```
public void setJoinCondition(TExpression onCondition)
```
  - getLeftMostJoinExpr
```
public TJoinExpr getLeftMostJoinExpr()
```
  - setNestedParen
```
public void setNestedParen(int nestedParen)
```
  - setUsingColumns
```
public void setUsingColumns(TObjectNameList usingColumns)
```
  - setOnCondition
```
public void setOnCondition(TExpression onCondition)
```
  - getMatchCondition
```
public TExpression getMatchCondition()
```
  - setMatchCondition
```
public void setMatchCondition(TExpression matchCondition)
```
  - 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

Class TJoinExpr

Field Summary

Fields inherited from class gudusoft.gsqlparser.nodes.TParseTreeNode

Constructor Summary

Method Summary

Methods inherited from class gudusoft.gsqlparser.nodes.TNodeWithAliasClause

Methods inherited from class gudusoft.gsqlparser.nodes.TParseTreeNode

Methods inherited from class Object

Methods inherited from interface Iterator

Field Detail

usingColumns

onCondition

original_jontype

Constructor Detail

TJoinExpr

Method Detail

getJoin_using_alias

initAttributes

getAttributes

getRelationName

size

setLeftTable

setRightTable

getLeftTable

getRightTable

incNestedParen

getNestedParen

getUsingColumns

getOnCondition

getJointype

setJointype

getLeftOperand

getRightOperand

setLeftOperand

setRightOperand

init

init

setJoinCondition

setJoinCondition

getLeftMostJoinExpr

setNestedParen

setUsingColumns

setOnCondition

getMatchCondition

setMatchCondition

accept

acceptChildren