TaQLNodeHandler.h

Classes

TaQLNodeHandler -- Class to handle the nodes in the raw TaQL parse tree. (full description)

TaQLNodeHRValue -- Class containing the result value of the handling of a TaQLNode. (full description)

class TaQLNodeHandler : public TaQLNodeVisitor

Interface

Public Members

virtual ~TaQLNodeHandler()

TaQLNodeResult handleTree (const TaQLNode& tree, const std::vector<const vector*>&)

virtual TaQLNodeResult visitConstNode (const TaQLConstNodeRep& node)

virtual TaQLNodeResult visitUnaryNode (const TaQLUnaryNodeRep& node)

virtual TaQLNodeResult visitBinaryNode (const TaQLBinaryNodeRep& node)

virtual TaQLNodeResult visitMultiNode (const TaQLMultiNodeRep& node)

virtual TaQLNodeResult visitFuncNode (const TaQLFuncNodeRep& node)

virtual TaQLNodeResult visitRangeNode (const TaQLRangeNodeRep& node)

virtual TaQLNodeResult visitIndexNode (const TaQLIndexNodeRep& node)

virtual TaQLNodeResult visitKeyColNode (const TaQLKeyColNodeRep& node)

virtual TaQLNodeResult visitTableNode (const TaQLTableNodeRep& node)

virtual TaQLNodeResult visitColNode (const TaQLColNodeRep& node)

virtual TaQLNodeResult visitColumnsNode (const TaQLColumnsNodeRep& node)

virtual TaQLNodeResult visitJoinNode (const TaQLJoinNodeRep& node)

virtual TaQLNodeResult visitSortKeyNode (const TaQLSortKeyNodeRep& node)

virtual TaQLNodeResult visitSortNode (const TaQLSortNodeRep& node)

virtual TaQLNodeResult visitLimitOffNode (const TaQLLimitOffNodeRep& node)

virtual TaQLNodeResult visitGivingNode (const TaQLGivingNodeRep& node)

virtual TaQLNodeResult visitUpdExprNode (const TaQLUpdExprNodeRep& node)

virtual TaQLNodeResult visitSelectNode (const TaQLSelectNodeRep& node)

virtual TaQLNodeResult visitUpdateNode (const TaQLUpdateNodeRep& node)

virtual TaQLNodeResult visitInsertNode (const TaQLInsertNodeRep& node)

virtual TaQLNodeResult visitDeleteNode (const TaQLDeleteNodeRep& node)

virtual TaQLNodeResult visitCalcNode (const TaQLCalcNodeRep& node)

virtual TaQLNodeResult visitCreTabNode (const TaQLCreTabNodeRep& node)

virtual TaQLNodeResult visitColSpecNode (const TaQLColSpecNodeRep& node)

virtual TaQLNodeResult visitRecFldNode (const TaQLRecFldNodeRep& node)

static const TaQLNodeHRValue& getHR (const TaQLNodeResult&)

Private Members

TableParseSelect* pushStack (TableParseSelect::CommandType)

TableParseSelect* topStack() const

void popStack()

void clearStack()

TaQLNodeResult handleSelect (const TaQLSelectNodeRep& node, Bool doExec)

void handleTables (const TaQLMultiNode&)

void handleWhere (const TaQLNode&)

void handleUpdate (const TaQLMultiNode&)

void handleInsCol (const TaQLMultiNode&)

void handleInsVal (const TaQLNode&)

void handleColSpec (const TaQLMultiNode&)

Record handleRecord (const TaQLMultiNodeRep*)

void handleRecFld (const TaQLNode&, Record&)

void handleMultiRecFld (const String& fldName, const TaQLMultiNodeRep* node, Record& rec)

int checkConstDtype (int dt1, int dt2)

Description

Review Status

Programs:

Tests:

• tTableGram

Prerequisite

• TaQLNode
• Note 199 describing TaQL

Synopsis

Motivation

• The full command is parsed before any processing is done. So in case of a parse error, no possibly expensive processing has been done yet.
• In the future query optimization can be done in an easier way.
• Nested parsing is not possible. In case a Table is opened with a virtual TaQL column, the parsing of that TaQL string does not interfere with parsing the TaQL command.
• It is possible to use expressions in the column list. That could not be done before, because the column list was parsed/processed before the table list.

  Member Description

  virtual ~TaQLNodeHandler()

  TaQLNodeResult handleTree (const TaQLNode& tree, const std::vector<const vector*>&)

  Handle and process the raw parse tree. The result contains a Table or TableExprNode object.

  virtual TaQLNodeResult visitConstNode (const TaQLConstNodeRep& node)
  virtual TaQLNodeResult visitUnaryNode (const TaQLUnaryNodeRep& node)
  virtual TaQLNodeResult visitBinaryNode (const TaQLBinaryNodeRep& node)
  virtual TaQLNodeResult visitMultiNode (const TaQLMultiNodeRep& node)
  virtual TaQLNodeResult visitFuncNode (const TaQLFuncNodeRep& node)
  virtual TaQLNodeResult visitRangeNode (const TaQLRangeNodeRep& node)
  virtual TaQLNodeResult visitIndexNode (const TaQLIndexNodeRep& node)
  virtual TaQLNodeResult visitKeyColNode (const TaQLKeyColNodeRep& node)
  virtual TaQLNodeResult visitTableNode (const TaQLTableNodeRep& node)
  virtual TaQLNodeResult visitColNode (const TaQLColNodeRep& node)
  virtual TaQLNodeResult visitColumnsNode (const TaQLColumnsNodeRep& node)
  virtual TaQLNodeResult visitJoinNode (const TaQLJoinNodeRep& node)
  virtual TaQLNodeResult visitSortKeyNode (const TaQLSortKeyNodeRep& node)
  virtual TaQLNodeResult visitSortNode (const TaQLSortNodeRep& node)
  virtual TaQLNodeResult visitLimitOffNode (const TaQLLimitOffNodeRep& node)
  virtual TaQLNodeResult visitGivingNode (const TaQLGivingNodeRep& node)
  virtual TaQLNodeResult visitUpdExprNode (const TaQLUpdExprNodeRep& node)
  virtual TaQLNodeResult visitSelectNode (const TaQLSelectNodeRep& node)
  virtual TaQLNodeResult visitUpdateNode (const TaQLUpdateNodeRep& node)
  virtual TaQLNodeResult visitInsertNode (const TaQLInsertNodeRep& node)
  virtual TaQLNodeResult visitDeleteNode (const TaQLDeleteNodeRep& node)
  virtual TaQLNodeResult visitCalcNode (const TaQLCalcNodeRep& node)
  virtual TaQLNodeResult visitCreTabNode (const TaQLCreTabNodeRep& node)
  virtual TaQLNodeResult visitColSpecNode (const TaQLColSpecNodeRep& node)
  virtual TaQLNodeResult visitRecFldNode (const TaQLRecFldNodeRep& node)

  Define the functions to visit each node type.

  static const TaQLNodeHRValue& getHR (const TaQLNodeResult&)

  Get the actual result object from the result.

  TableParseSelect* pushStack (TableParseSelect::CommandType)

  Push a new TableParseSelect on the stack.

  TableParseSelect* topStack() const

  Get the top of the TableParseSelect stack.

  void popStack()

  Pop the top from the TableParseSelect stack.

  void clearStack()

  Clear the select stack.

  TaQLNodeResult handleSelect (const TaQLSelectNodeRep& node, Bool doExec)

  Handle the select command. Optionally the command is not executed (needed for the EXISTS operator).

  void handleTables (const TaQLMultiNode&)

  Handle a MultiNode containing table info.

  void handleWhere (const TaQLNode&)

  Handle the WHERE clause.

  void handleUpdate (const TaQLMultiNode&)

  Handle the UPDATE SET clause.

  void handleInsCol (const TaQLMultiNode&)

  Handle the INSERT columns.

  void handleInsVal (const TaQLNode&)

  Handle the INSERT values.

  void handleColSpec (const TaQLMultiNode&)

  Handle a column specification in a create table.

  Record handleRecord (const TaQLMultiNodeRep*)

  Handle a record specification.

  void handleRecFld (const TaQLNode&, Record&)

  Handle a record field and add it to the Record.

  void handleMultiRecFld (const String& fldName, const TaQLMultiNodeRep* node, Record& rec)

  Handle a record field with multiple values and add it to the Record. The field can be a record or a vector of values.

  int checkConstDtype (int dt1, int dt2)

  Determine 'highest' constant data type and check if they match.

  ---

  class TaQLNodeHRValue: public TaQLNodeResultRep

  Interface

  Public Members

  TaQLNodeHRValue() : itsInt(-1), itsElem(0), itsSet(0), itsNames(0)

  TaQLNodeHRValue (const TableExprNode& expr) : itsInt(-1), itsExpr(expr), itsElem(0), itsSet(0), itsNames(0)

  virtual ~TaQLNodeHRValue()

  Int getInt() const

  const String& getString() const

  const String& getAlias() const

  const String& getDtype() const

  const Record& getRecord() const

  const Table& getTable() const

  const TableExprNode& getExpr() const

  const TableExprNodeSetElem* getElem() const

  const TableExprNodeSet& getExprSet() const

  const Vector<String>* getNames() const

  void setInt (Int ival)

  void setString (const String& str)

  void setAlias (const String& alias)

  void setDtype (const String& dtype)

  void setRecord (const Record& record)

  void setTable (const Table& table)

  void setExpr (const TableExprNode& expr)

  void setElem (TableExprNodeSetElem* elem)

  void setExprSet (TableExprNodeSet* set)

  void setNames (Vector<String>* names)

  Description

  Review Status

  Programs:

  Tests:

  • tTableGram

  Prerequisite

  • TaQLNodeResult
  • TaQLNodeHandler
  • Note 199 describing TaQL

  Synopsis

  TaQLNodeHRValue is a specialization of class TaQLNodeResultRep. It contains the values resulting from handling a particular node. The object is effectively a collection of all possible values that need to be returned. Which values are filled in, depends on which node has been processed. The getHR function in TaQLNodeHandler is very useful to extract/cast the TaQLNodeHRValue object from the general TaQLNodeResult object.

  Member Description

  TaQLNodeHRValue() : itsInt(-1), itsElem(0), itsSet(0), itsNames(0)

  TaQLNodeHRValue (const TableExprNode& expr) : itsInt(-1), itsExpr(expr), itsElem(0), itsSet(0), itsNames(0)

  virtual ~TaQLNodeHRValue()

  Int getInt() const
  const String& getString() const
  const String& getAlias() const
  const String& getDtype() const
  const Record& getRecord() const
  const Table& getTable() const
  const TableExprNode& getExpr() const
  const TableExprNodeSetElem* getElem() const
  const TableExprNodeSet& getExprSet() const
  const Vector<String>* getNames() const

  Get the values.

  void setInt (Int ival)
  void setString (const String& str)
  void setAlias (const String& alias)
  void setDtype (const String& dtype)
  void setRecord (const Record& record)
  void setTable (const Table& table)
  void setExpr (const TableExprNode& expr)
  void setElem (TableExprNodeSetElem* elem)
  void setExprSet (TableExprNodeSet* set)
  void setNames (Vector<String>* names)

  Set the values. If a pointer is given, it takes over the pointer.