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TaQLNodeHandler.h
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1 //# TaQLNodeHandler.h: Classes to handle the nodes in the raw TaQL parse tree
2 //# Copyright (C) 2005
3 //# Associated Universities, Inc. Washington DC, USA.
4 //#
5 //# This library is free software; you can redistribute it and/or modify it
6 //# under the terms of the GNU Library General Public License as published by
7 //# the Free Software Foundation; either version 2 of the License, or (at your
8 //# option) any later version.
9 //#
10 //# This library is distributed in the hope that it will be useful, but WITHOUT
11 //# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 //# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
13 //# License for more details.
14 //#
15 //# You should have received a copy of the GNU Library General Public License
16 //# along with this library; if not, write to the Free Software Foundation,
17 //# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
18 //#
19 //# Correspondence concerning AIPS++ should be addressed as follows:
20 //# Internet email: aips2-request@nrao.edu.
21 //# Postal address: AIPS++ Project Office
22 //# National Radio Astronomy Observatory
23 //# 520 Edgemont Road
24 //# Charlottesville, VA 22903-2475 USA
25 //#
26 //# $Id$
27 
28 #ifndef TABLES_TAQLNODEHANDLER_H
29 #define TABLES_TAQLNODEHANDLER_H
30 
31 //# Includes
32 #include <casacore/casa/aips.h>
40 #include <vector>
41 
42 namespace casacore { //# NAMESPACE CASACORE - BEGIN
43 
44 //# Forward Declarations
45 class TaQLNodeHRValue;
46 
47 
48 // <summary>
49 // Class to handle the nodes in the raw TaQL parse tree.
50 // </summary>
51 
52 // <use visibility=local>
53 
54 // <reviewed reviewer="" date="" tests="tTableGram">
55 // </reviewed>
56 
57 // <prerequisite>
58 //# Classes you should understand before using this one.
59 // <li> <linkto class=TaQLNode>TaQLNode</linkto>
60 // <li> Note 199 describing
61 // <a href="../notes/199.html">
62 // TaQL</a>
63 // </prerequisite>
64 
65 // <synopsis>
66 // TaQLNodeHandler is a specialization of class
67 // <linkto class=TaQLNodeVisitor>TaQLNodeVisitor</linkto>.
68 // It processes the raw TaQL parse tree generated by TableGram.
69 // The processing is done in a recursive way. It starts at the top
70 // (which is a SELECT, UPDATE, etc. expression) and the processing
71 // results of a query are stored in a TableParseSelect object.
72 // These objects are kept in a stack for possible nested queries.
73 // After a query is fully processed, it is executed. Usually the result
74 // is a table; only a CALC command gives a TableExprNode as result.
75 // </synopsis>
76 
77 // <motivation>
78 // Separating the raw query parsing from the query processing has
79 // several advantages compared to the old situation where parsing
80 // and processing were combined.
81 // <ul>
82 // <li> The full command is parsed before any processing is done.
83 // So in case of a parse error, no possibly expensive processing
84 // has been done yet.
85 // <li> In the future query optimization can be done in an easier way.
86 // <li> Nested parsing is not possible. In case a Table is opened
87 // with a virtual TaQL column, the parsing of that TaQL string
88 // does not interfere with parsing the TaQL command.
89 // <li> It is possible to use expressions in the column list.
90 // That could not be done before, because the column list was
91 // parsed/processed before the table list.
92 // </ul>
93 // </motivation>
94 
96 {
97 public:
98  virtual ~TaQLNodeHandler();
99 
100  // Handle and process the raw parse tree.
101  // The result contains a Table or TableExprNode object.
102  TaQLNodeResult handleTree (const TaQLNode& tree,
103  const std::vector<const Table*>&);
104 
105  // Define the functions to visit each node type.
106  // <group>
107  virtual TaQLNodeResult visitConstNode (const TaQLConstNodeRep& node);
108  virtual TaQLNodeResult visitRegexNode (const TaQLRegexNodeRep& node);
109  virtual TaQLNodeResult visitUnaryNode (const TaQLUnaryNodeRep& node);
110  virtual TaQLNodeResult visitBinaryNode (const TaQLBinaryNodeRep& node);
111  virtual TaQLNodeResult visitMultiNode (const TaQLMultiNodeRep& node);
112  virtual TaQLNodeResult visitFuncNode (const TaQLFuncNodeRep& node);
113  virtual TaQLNodeResult visitRangeNode (const TaQLRangeNodeRep& node);
114  virtual TaQLNodeResult visitIndexNode (const TaQLIndexNodeRep& node);
115  virtual TaQLNodeResult visitKeyColNode (const TaQLKeyColNodeRep& node);
116  virtual TaQLNodeResult visitTableNode (const TaQLTableNodeRep& node);
117  virtual TaQLNodeResult visitColNode (const TaQLColNodeRep& node);
118  virtual TaQLNodeResult visitColumnsNode (const TaQLColumnsNodeRep& node);
119  virtual TaQLNodeResult visitJoinNode (const TaQLJoinNodeRep& node);
120  virtual TaQLNodeResult visitGroupNode (const TaQLGroupNodeRep& node);
121  virtual TaQLNodeResult visitSortKeyNode (const TaQLSortKeyNodeRep& node);
122  virtual TaQLNodeResult visitSortNode (const TaQLSortNodeRep& node);
124  virtual TaQLNodeResult visitGivingNode (const TaQLGivingNodeRep& node);
125  virtual TaQLNodeResult visitUpdExprNode (const TaQLUpdExprNodeRep& node);
126  virtual TaQLNodeResult visitSelectNode (const TaQLSelectNodeRep& node);
127  virtual TaQLNodeResult visitUpdateNode (const TaQLUpdateNodeRep& node);
128  virtual TaQLNodeResult visitInsertNode (const TaQLInsertNodeRep& node);
129  virtual TaQLNodeResult visitDeleteNode (const TaQLDeleteNodeRep& node);
130  virtual TaQLNodeResult visitCountNode (const TaQLCountNodeRep& node);
131  virtual TaQLNodeResult visitCalcNode (const TaQLCalcNodeRep& node);
132  virtual TaQLNodeResult visitCreTabNode (const TaQLCreTabNodeRep& node);
133  virtual TaQLNodeResult visitColSpecNode (const TaQLColSpecNodeRep& node);
134  virtual TaQLNodeResult visitRecFldNode (const TaQLRecFldNodeRep& node);
135  virtual TaQLNodeResult visitUnitNode (const TaQLUnitNodeRep& node);
136  virtual TaQLNodeResult visitAltTabNode (const TaQLAltTabNodeRep& node);
137  virtual TaQLNodeResult visitAddColNode (const TaQLAddColNodeRep& node);
138  virtual TaQLNodeResult visitSetKeyNode (const TaQLSetKeyNodeRep& node);
139  virtual TaQLNodeResult visitRenDropNode (const TaQLRenDropNodeRep& node);
140  virtual TaQLNodeResult visitAddRowNode (const TaQLAddRowNodeRep& node);
141  virtual TaQLNodeResult visitConcTabNode (const TaQLConcTabNodeRep& node);
142  virtual TaQLNodeResult visitShowNode (const TaQLShowNodeRep& node);
143  virtual TaQLNodeResult visitCopyColNode (const TaQLCopyColNodeRep& node);
144  virtual TaQLNodeResult visitDropTabNode (const TaQLDropTabNodeRep& node);
145  // </group>
146 
147  // Get the actual result object from the result.
148  static const TaQLNodeHRValue& getHR (const TaQLNodeResult&);
149 
150 private:
151  // Push a new TableParseSelect on the stack.
153 
154  // Get the top of the TableParseSelect stack.
155  TableParseSelect* topStack() const;
156 
157  // Pop the top from the TableParseSelect stack.
158  void popStack();
159 
160  // Clear the select stack.
161  void clearStack();
162 
163  // Handle the select command.
164  // Optionally the command is not executed (needed for the EXISTS operator).
165  TaQLNodeResult handleSelect (const TaQLSelectNodeRep& node, Bool doExec);
166 
167  // Handle a table name or temptable number in the given node
168  // and put it in the value result.
169  void handleTableName (TaQLNodeHRValue* hrval, const TaQLNode& node);
170 
171  // Handle a MultiNode containing table info.
172  void handleTables (const TaQLMultiNode&, Bool addToFromList=True);
173 
174  // Make a ConcatTable from a nested set of tables.
175  Table makeConcatTable (const TaQLMultiNodeRep& node);
176 
177  // Handle the WHERE clause.
178  void handleWhere (const TaQLNode&);
179 
180  // Handle the HAVING clause.
181  void handleHaving (const TaQLNode&);
182 
183  // Handle the UPDATE SET clause.
184  void handleUpdate (const TaQLMultiNode&);
185 
186  // Handle the INSERT columns.
187  void handleInsCol (const TaQLMultiNode&);
188 
189  // Handle the INSERT values.
190  void handleInsVal (const TaQLNode&);
191 
192  // Handle the possible LIKE table DROP COLUMN part.
193  void handleLikeDrop (const TaQLMultiNode& node);
194 
195  // Handle a column specification in a create table or add column.
196  void handleColSpecs (const TaQLMultiNode&);
197 
198  // Handle a Multi RecFld representing a Record.
199  Record handleMultiRecFld (const TaQLNode& node);
200 
201 
202  //# Use vector instead of stack because it has random access
203  //# (which is used in TableParse.cc).
204  std::vector<TableParseSelect*> itsStack;
205  //# The temporary tables referred to by $i in the TaQL string.
206  std::vector<const Table*> itsTempTables;
207 };
208 
209 
210 // <summary>
211 // Class containing the result value of the handling of a TaQLNode.
212 // </summary>
213 
214 // <use visibility=local>
215 
216 // <reviewed reviewer="" date="" tests="tTableGram">
217 // </reviewed>
218 
219 // <prerequisite>
220 //# Classes you should understand before using this one.
221 // <li> <linkto class=TaQLNode>TaQLNodeResult</linkto>
222 // <li> <linkto class=TaQLNode>TaQLNodeHandler</linkto>
223 // <li> Note 199 describing
224 // <a href="../notes/199.html">
225 // TaQL</a>
226 // </prerequisite>
227 
228 // <synopsis>
229 // TaQLNodeHRValue is a specialization of class
230 // <linkto class=TaQLNodeResultRep>TaQLNodeResultRep</linkto>.
231 // It contains the values resulting from handling a particular node.
232 // The object is effectively a collection of all possible values that
233 // need to be returned. Which values are filled in, depends on which node
234 // has been processed.
235 // <note> The getHR function in TaQLNodeHandler is very useful to
236 // extract/cast the TaQLNodeHRValue object from the general
237 // TaQLNodeResult object.
238 // </note>
239 // </synopsis>
240 
242 {
243 public:
245  : itsInt(-1), itsElem(0), itsSet(0), itsNames(0) {}
247  : itsInt(-1), itsExpr(expr), itsElem(0), itsSet(0), itsNames(0) {}
248  virtual ~TaQLNodeHRValue();
249 
250  // Get the values.
251  // <group>
252  Int getInt() const
253  { return itsInt; }
254  const String& getString() const
255  { return itsString; }
256  const String& getAlias() const
257  { return itsAlias; }
258  const String& getNameMask() const
259  { return itsNameMask; }
260  const String& getDtype() const
261  { return itsDtype; }
262  const Record& getRecord() const
263  { return itsRecord; }
265  { return itsVH; }
266  const Table& getTable() const
267  { return itsTable; }
268  const TableExprNode& getExpr() const
269  { return itsExpr; }
271  { return itsElem; }
273  { return *itsSet; }
274  const Vector<String>* getNames() const
275  { return itsNames; }
276  // </group>
277 
278  // Set the values.
279  // If a pointer is given, it takes over the pointer.
280  // <group>
281  void setInt (Int ival)
282  { itsInt = ival; }
283  void setString (const String& str)
284  { itsString = str; }
285  void setAlias (const String& alias)
286  { itsAlias = alias; }
287  void setNameMask (const String& nameMask)
288  { itsNameMask = nameMask; }
289  void setDtype (const String& dtype)
290  { itsDtype = dtype; }
291  void setRecord (const Record& record)
292  { itsRecord = record; }
293  void setValueHolder (const ValueHolder& vh)
294  { itsVH = vh; }
295  void setTable (const Table& table)
296  { itsTable = table; }
297  void setExpr (const TableExprNode& expr)
298  { itsExpr = expr; }
300  { itsElem = elem; }
302  { itsSet = set; }
303  void setNames (Vector<String>* names)
304  { itsNames = names; }
305  // </group>
306 
307 private:
320 };
321 
322 
323 //# This function can only be implemented after TaQLNodeHRBase is declared.
325 {
326  return *(TaQLNodeHRValue*)(res.getRep());
327 }
328 
329 
330 
331 } //# NAMESPACE CASACORE - END
332 
333 #endif
const ValueHolder & getValueHolder() const
virtual TaQLNodeResult visitKeyColNode(const TaQLKeyColNodeRep &node)
void setExpr(const TableExprNode &expr)
A 1-D Specialization of the Array class.
Definition: ArrayFwd.h:9
Raw TaQL parse tree node defining a count command.
Definition: TaQLNodeDer.h:835
int Int
Definition: aipstype.h:50
void popStack()
Pop the top from the TableParseSelect stack.
std::vector< TableParseSelect * > itsStack
const TableExprNode & getExpr() const
Abstract base class to hold the result of a visit to the node tree.
void handleTableName(TaQLNodeHRValue *hrval, const TaQLNode &node)
Handle a table name or temptable number in the given node and put it in the value result...
TableExprNodeSetElem * itsElem
void setAlias(const String &alias)
Raw TaQL parse tree node defining an alter table add rows command.
Definition: TaQLNodeDer.h:1250
void setNames(Vector< String > *names)
Raw TaQL parse tree node defining a select command.
Definition: TaQLNodeDer.h:788
Main interface class to a read/write table.
Definition: Table.h:157
void setElem(TableExprNodeSetElem *elem)
Raw TaQL parse tree node defining an update command.
Definition: TaQLNodeDer.h:868
void setString(const String &str)
virtual TaQLNodeResult visitConstNode(const TaQLConstNodeRep &node)
Define the functions to visit each node type.
virtual TaQLNodeResult visitDeleteNode(const TaQLDeleteNodeRep &node)
Class to hold multiple table expression nodes.
Definition: ExprNodeSet.h:310
virtual TaQLNodeResult visitTableNode(const TaQLTableNodeRep &node)
Handle class for a table column expression tree.
Definition: ExprNode.h:156
void setExprSet(TableExprNodeSet *set)
const String & getNameMask() const
void setRecord(const Record &record)
Raw TaQL parse tree node defining a range.
Definition: TaQLNodeDer.h:324
Raw TaQL parse tree node defining an alter table set keyword command.
Definition: TaQLNodeDer.h:1223
virtual TaQLNodeResult visitInsertNode(const TaQLInsertNodeRep &node)
Raw TaQL parse tree node defining a constant value.
Definition: TaQLNodeDer.h:61
virtual TaQLNodeResult visitSelectNode(const TaQLSelectNodeRep &node)
Raw TaQL parse tree node defining a create table command.
Definition: TaQLNodeDer.h:1007
void handleHaving(const TaQLNode &)
Handle the HAVING clause.
Raw TaQL parse tree node defining an index in a array.
Definition: TaQLNodeDer.h:358
virtual TaQLNodeResult visitSortNode(const TaQLSortNodeRep &node)
Raw TaQL parse tree node defining a calc command.
Definition: TaQLNodeDer.h:973
virtual TaQLNodeResult visitCreTabNode(const TaQLCreTabNodeRep &node)
Int getInt() const
Get the values.
Raw TaQL parse tree node defining a list of nodes.
Definition: TaQLNodeDer.h:247
virtual TaQLNodeResult visitUpdExprNode(const TaQLUpdExprNodeRep &node)
void clearStack()
Clear the select stack.
virtual TaQLNodeResult visitAddRowNode(const TaQLAddRowNodeRep &node)
void handleColSpecs(const TaQLMultiNode &)
Handle a column specification in a create table or add column.
const Record & getRecord() const
std::vector< const Table * > itsTempTables
virtual TaQLNodeResult visitShowNode(const TaQLShowNodeRep &node)
Select-class for flex/bison scanner/parser for TableParse.
Definition: TableParse.h:388
Class to handle the nodes in the raw TaQL parse tree.
Raw TaQL parse tree node defining a delete command.
Definition: TaQLNodeDer.h:940
void handleUpdate(const TaQLMultiNode &)
Handle the UPDATE SET clause.
TableParseSelect * pushStack(TableParseSelect::CommandType)
Push a new TableParseSelect on the stack.
virtual TaQLNodeResult visitRegexNode(const TaQLRegexNodeRep &node)
Envelope class for a node containing a list of nodes.
Definition: TaQLNode.h:228
Raw TaQL parse tree node defining a table.
Definition: TaQLNodeDer.h:448
Class to hold the table expression nodes for an element in a set.
Definition: ExprNodeSet.h:93
Raw TaQL parse tree node defining an alter table copy column command.
Definition: TaQLNodeDer.h:1335
virtual TaQLNodeResult visitMultiNode(const TaQLMultiNodeRep &node)
virtual TaQLNodeResult visitRangeNode(const TaQLRangeNodeRep &node)
virtual TaQLNodeResult visitGivingNode(const TaQLGivingNodeRep &node)
Raw TaQL parse tree node defining a groupby list.
Definition: TaQLNodeDer.h:541
Raw TaQL parse tree node defining a giving expression list.
Definition: TaQLNodeDer.h:668
Raw TaQL parse tree node defining a unary operator.
Definition: TaQLNodeDer.h:154
Raw TaQL parse tree node defining a constant regex value.
Definition: TaQLNodeDer.h:118
Raw TaQL parse tree node defining a record field.
Definition: TaQLNodeDer.h:1074
A holder for a value of any basic Casacore data type.
Definition: ValueHolder.h:68
const TableExprNodeSet & getExprSet() const
virtual TaQLNodeResult visitJoinNode(const TaQLJoinNodeRep &node)
virtual TaQLNodeResult visitBinaryNode(const TaQLBinaryNodeRep &node)
TaQLNodeResult handleSelect(const TaQLSelectNodeRep &node, Bool doExec)
Handle the select command.
Raw TaQL parse tree node defining an alter table command.
Definition: TaQLNodeDer.h:1277
const String & getAlias() const
virtual TaQLNodeResult visitIndexNode(const TaQLIndexNodeRep &node)
Raw TaQL parse tree node defining a keyword or column name.
Definition: TaQLNodeDer.h:418
virtual TaQLNodeResult visitSortKeyNode(const TaQLSortKeyNodeRep &node)
virtual TaQLNodeResult visitRenDropNode(const TaQLRenDropNodeRep &node)
virtual TaQLNodeResult visitConcTabNode(const TaQLConcTabNodeRep &node)
virtual TaQLNodeResult visitUnaryNode(const TaQLUnaryNodeRep &node)
A hierarchical collection of named fields of various types.
Definition: Record.h:180
bool Bool
Define the standard types used by Casacore.
Definition: aipstype.h:42
Raw TaQL parse tree node defining a function.
Definition: TaQLNodeDer.h:294
virtual TaQLNodeResult visitUnitNode(const TaQLUnitNodeRep &node)
void handleInsVal(const TaQLNode &)
Handle the INSERT values.
virtual TaQLNodeResult visitRecFldNode(const TaQLRecFldNodeRep &node)
void setTable(const Table &table)
static const TaQLNodeHRValue & getHR(const TaQLNodeResult &)
Get the actual result object from the result.
Record handleMultiRecFld(const TaQLNode &node)
Handle a Multi RecFld representing a Record.
const TaQLNodeResultRep * getRep() const
Get the actual underlying object.
Raw TaQL parse tree node defining an alter table rename or drop command.
Definition: TaQLNodeDer.h:1195
Raw TaQL parse tree node defining a create column specification.
Definition: TaQLNodeDer.h:1043
virtual TaQLNodeResult visitSetKeyNode(const TaQLSetKeyNodeRep &node)
virtual TaQLNodeResult visitCopyColNode(const TaQLCopyColNodeRep &node)
virtual TaQLNodeResult visitFuncNode(const TaQLFuncNodeRep &node)
Raw TaQL parse tree node defining a unit.
Definition: TaQLNodeDer.h:1108
TableParseSelect * topStack() const
Get the top of the TableParseSelect stack.
Raw TaQL parse tree node defining a column update expression.
Definition: TaQLNodeDer.h:701
virtual TaQLNodeResult visitColumnsNode(const TaQLColumnsNodeRep &node)
virtual TaQLNodeResult visitColSpecNode(const TaQLColSpecNodeRep &node)
const String & getString() const
void setNameMask(const String &nameMask)
Vector< String > * itsNames
Raw TaQL parse tree node defining a DROP TABLE command.
Definition: TaQLNodeDer.h:1363
void setValueHolder(const ValueHolder &vh)
virtual TaQLNodeResult visitDropTabNode(const TaQLDropTabNodeRep &node)
void setDtype(const String &dtype)
const String & getDtype() const
Envelope class to hold the result of a visit to the node tree.
const TableExprNodeSetElem * getElem() const
Raw TaQL parse tree node defining a limit/offset expression.
Definition: TaQLNodeDer.h:639
TaQLNodeHRValue(const TableExprNode &expr)
TableExprNodeSet * itsSet
Raw TaQL parse tree node defining a sort key.
Definition: TaQLNodeDer.h:573
Raw TaQL parse tree node defining a sort list.
Definition: TaQLNodeDer.h:606
void handleTables(const TaQLMultiNode &, Bool addToFromList=True)
Handle a MultiNode containing table info.
void handleLikeDrop(const TaQLMultiNode &node)
Handle the possible LIKE table DROP COLUMN part.
virtual TaQLNodeResult visitLimitOffNode(const TaQLLimitOffNodeRep &node)
Raw TaQL parse tree node defining an alter table add column command.
Definition: TaQLNodeDer.h:1167
String: the storage and methods of handling collections of characters.
Definition: String.h:225
Raw TaQL parse tree node defining a select column expression.
Definition: TaQLNodeDer.h:480
void setInt(Int ival)
Set the values.
const Table & getTable() const
Raw TaQL parse tree node defining a show command.
Definition: TaQLNodeDer.h:1308
Raw TaQL parse tree node defining a select column list.
Definition: TaQLNodeDer.h:512
virtual TaQLNodeResult visitGroupNode(const TaQLGroupNodeRep &node)
Raw TaQL parse tree node defining a join operation.
Definition: TaQLNodeDer.h:389
Envelope class for a node in the raw TaQL parse tree.
Definition: TaQLNode.h:83
virtual TaQLNodeResult visitAltTabNode(const TaQLAltTabNodeRep &node)
void handleInsCol(const TaQLMultiNode &)
Handle the INSERT columns.
virtual TaQLNodeResult visitAddColNode(const TaQLAddColNodeRep &node)
Class to visit the nodes in the raw TaQL parse tree.
Class containing the result value of the handling of a TaQLNode.
TaQLNodeResult handleTree(const TaQLNode &tree, const std::vector< const Table * > &)
Handle and process the raw parse tree.
virtual TaQLNodeResult visitCalcNode(const TaQLCalcNodeRep &node)
void handleWhere(const TaQLNode &)
Handle the WHERE clause.
const Bool True
Definition: aipstype.h:43
Raw TaQL parse tree node defining a binary operator.
Definition: TaQLNodeDer.h:191
virtual TaQLNodeResult visitColNode(const TaQLColNodeRep &node)
Raw TaQL parse tree node defining an alter table command.
Definition: TaQLNodeDer.h:1136
virtual TaQLNodeResult visitCountNode(const TaQLCountNodeRep &node)
Raw TaQL parse tree node defining an insert command.
Definition: TaQLNodeDer.h:905
virtual TaQLNodeResult visitUpdateNode(const TaQLUpdateNodeRep &node)
Table makeConcatTable(const TaQLMultiNodeRep &node)
Make a ConcatTable from a nested set of tables.
const Vector< String > * getNames() const