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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997, 2013 Oracle and/or its affiliates. All rights reserved.
*
* $Id$
*/
/*
* NOTE: AccessExample changed to test Db.key_range. We made a global
* change of /AccessExample/TestKeyRange/, the only other changes are
* marked with comments that are notated as 'ADDED'.
*/
#include <sys/types.h>
#include <iostream>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#ifndef _MSC_VER
#include <unistd.h>
#endif
#include <iomanip>
#include <db_cxx.h>
using namespace std;
class TestKeyRange
{
public:
TestKeyRange();
void run();
private:
static const char FileName[];
// no need for copy and assignment
TestKeyRange(const TestKeyRange &);
void operator = (const TestKeyRange &);
};
static void usage(); // forward
int main(int argc, char *argv[])
{
if (argc > 1) {
usage();
}
// Use a try block just to report any errors.
// An alternate approach to using exceptions is to
// use error models (see DbEnv::set_error_model()) so
// that error codes are returned for all Berkeley DB methods.
//
try {
TestKeyRange app;
app.run();
return 0;
}
catch (DbException &dbe) {
cerr << "TestKeyRange: " << dbe.what() << "\n";
return 1;
}
}
static void usage()
{
cerr << "usage: TestKeyRange\n";
exit(1);
}
const char TestKeyRange::FileName[] = "access.db";
TestKeyRange::TestKeyRange()
{
}
void TestKeyRange::run()
{
// Remove the previous database.
(void)unlink(FileName);
// Create the database object.
// There is no environment for this simple example.
Db db(0, 0);
db.set_error_stream(&cerr);
db.set_errpfx("TestKeyRange");
db.set_pagesize(1024); /* Page size: 1K. */
db.set_cachesize(0, 32 * 1024, 0);
db.open(NULL, FileName, NULL, DB_BTREE, DB_CREATE, 0664);
//
// Insert records into the database, where the key is the user
// input and the data is the user input in reverse order.
//
char buf[1024];
char rbuf[1024];
char *t;
char *p;
int ret;
int len;
Dbt *firstkey = NULL;
char firstbuf[1024];
for (;;) {
cout << "input>";
cout.flush();
cin.getline(buf, sizeof(buf));
if (cin.eof())
break;
if ((len = strlen(buf)) <= 0)
continue;
for (t = rbuf, p = buf + (len - 1); p >= buf;)
*t++ = *p--;
*t++ = '\0';
Dbt key(buf, len + 1);
Dbt data(rbuf, len + 1);
if (firstkey == NULL) {
strcpy(firstbuf, buf);
firstkey = new Dbt(firstbuf, len + 1);
}
ret = db.put(0, &key, &data, DB_NOOVERWRITE);
if (ret == DB_KEYEXIST) {
cout << "Key " << buf << " already exists.\n";
}
cout << "\n";
}
// We put a try block around this section of code
// to ensure that our database is properly closed
// in the event of an error.
//
try {
// Acquire a cursor for the table.
Dbc *dbcp;
db.cursor(NULL, &dbcp, 0);
/*ADDED...*/
DB_KEY_RANGE range;
memset(&range, 0, sizeof(range));
db.key_range(NULL, firstkey, &range, 0);
printf("less: %f\n", range.less);
printf("equal: %f\n", range.equal);
printf("greater: %f\n", range.greater);
/*end ADDED*/
Dbt key;
Dbt data;
// Walk through the table, printing the key/data pairs.
while (dbcp->get(&key, &data, DB_NEXT) == 0) {
char *key_string = (char *)key.get_data();
char *data_string = (char *)data.get_data();
cout << key_string << " : " << data_string << "\n";
}
dbcp->close();
}
catch (DbException &dbe) {
cerr << "TestKeyRange: " << dbe.what() << "\n";
}
db.close(0);
}
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