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//------------------------------- relation.h -------------------------------
#ifndef _RELATION_H_
#define _RELATION_H_
#include <exception>
using namespace std;
#include <string.h>
#include <stdio.h>
#include "parseline.h"
#include "speclist.h"
class Relation {
enum { MAXNAME = 50, MAXFORMAT = 100, MAXWORD = 100,
MAXFILENAME = 100, MAXFIELD = 200, MAXFIELDS = 500,
MAXWIDTHLIST = 500,
MAXLINE = 1000, MAXDBLLINE = 2000, MAXLINES = 5000,
MAXRECORDS = 100000 };
struct {
char name[MAXNAME];
char datatype;
int position;
int printwidth;
} dict[MAXFIELDS];
Parseline *records[MAXRECORDS];
void print (FILE *fp);
char relfilename[MAXFILENAME];
Relation* istats (int whichfield);
Relation* dstats (int whichfield);
int current; // current record num
// Support functions
void copydict (Relation *source, Relation *dest);
void copydict2 (Relation *source1, Relation *source2, Relation *dest);
int xmatch1c (Parseline *x, int pos, char *comparison, char *fieldvalueC);
int xmatch1i (Parseline *x, int pos, char *comparison, char *fieldvalueC);
int xmatch1d (Parseline *x, int pos, char *comparison, char *fieldvalueC);
int match1 (Parseline *x, Spec comparison);
int match (Parseline *x, Speclist comps);
void makewidthline (char *line);
public:
int numrecords, numfields;
Relation () { numrecords = numfields = 0; }
Relation* select (Speclist specs);
void addfield (char *name, int pos, char type, int width);
void addfieldvalue (char *newfield, int recnum, char *newvalue);
void delrecord (int recnum);
void append (Relation *other);
Relation* difference (char *field1, Relation *other, char *field2);
Relation* copy ();
Relation* project (char *numlist);
void addrecord (Parseline *newrec);
void addrecord (char *someline);
void addrecord ();
void print ();
void printheader (FILE *fp);
void printfields (FILE *fp);
void load (char *filename);
void save (char *filename);
Relation* cross (Relation *other);
Relation* ejoin (Relation *other, char *whichf1, char *whichf2);
void sort (char *whichfield, bool ascending);
void sort ();
Relation* addseqnums ();
Relation* summarystats (char *whichfield);
int findfield (char *whichfield);
char getfieldtype (char *whichfield);
void showdict ();
void print1record (int recnum);
void info ();
void unique ();
void changefieldname (char *fieldname, char *newname);
void changefieldwidth (char *fieldname, int newwidth);
int getfieldwidth (char *fieldname);
// These will be useful for programs that directly deal with Relations
// (as opposed to the interface program).
int whichrec () { return current; }
int findrecord (char *fieldname, char *value);
int findrecord (char *fieldname, int value);
int findrecord (char *fieldname, double value);
void setcurrent (int recnum);
void advance ();
bool atend ();
char *getvalueC (char *fieldname);
int getvalueI (char *fieldname);
double getvalueD (char *fieldname);
void setvalue (char *fieldname, char *newvalueC);
void setvalue (char *fieldname, int newvalueI);
void setvalue (char *fieldname, double newvalueD);
void formatvalue (int recnum, int fieldnum, char *result,
size_t resultmaxlen);
/*
class RelationExcp: public exception
{
public:
RelationExcp(char * content): exception() {strncpy(excp_content, content, SIZE-1);}
const char *what() {
return excp_content;
}
private:
enum {SIZE = 20 };
char excp_content[SIZE];
};
*/
};
#endif
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