FileScanOperator.h Source File

00001 /*
00002  *  FileScanOperator.h
00003  *  DavisDB
00004  *
00005  *  Created by Mingmin Chen on 5/6/10.
00006  *  Copyright 2010 UCD. All rights reserved.
00007  *
00008  */
00009 
00010 
00011 #ifndef FILESCANOPERATOR_H_
00012 #define FILESCANOPERATOR_H_
00013 
00014 #include "IScanOperator.h"
00015 
00022 class FileScanOperator : public IScanOperator {
00023 public:
00024         FileScanOperator(const char* relation, int nAttributes, 
00025                                  const RelationAttributeInfo attributes[]);
00026         virtual ~FileScanOperator();
00027         
00028         // IQueryOperator methods
00029         ReturnCode openExecution();
00030         ReturnCode closeExecution();
00031         ReturnCode getNextRecord(Record* record);
00032         int getArity();
00033         void getSchema(RelationAttributeInfo attributes[]) ;
00034         void printSubtree(int indent);
00035 
00036         // IScanOperator methods
00037         ReturnCode openScan(int nAttribute, ComparisonOp op, const TypedValue* value);
00038         ReturnCode closeScan();
00039 
00040 private:
00041         RelationAttributeInfo* attributes_;
00042         char* relation_;
00043         int nAttributes_;
00044         int* offsets_;
00045         uint recordSize_;
00046         RecordFileManager* rm_;
00047         RecordFileHandle* rfh_;
00048         RecordFileScan rfs_;
00049         bool isScanOpen_;
00050 };
00051 
00052 #endif  // FILESCANOPERATOR_H_