I'm trying to replicate the simple C examples in the Getting Started
documentation. When I run createDb, it creates a database, but when I
run readDb, it gives me "get failed: DB_NOTFOUND: No matching key/data
pair found". I'm running 4.1.24 on SunOS 5.8. Any help would be
appreciated.

createDb.c:
#include <stdio.h>
#include <string.h>
#include <db.h>

int main(int argc, char *argv[]) {
DBT key, data;
DB *dbp;
int ret;

float money = 122.45;
char *description = "Grocery bill.";

ret = db_create(&dbp, NULL, 0);

if (ret != 0)
fprintf(stderr, "db_create failed: %s\n", db_strerror(ret));

ret = dbp->open(dbp, NULL, "my_db.db",
NULL, DB_BTREE, DB_CREATE, 0);

if (ret != 0)
fprintf(stderr, "open failed: %s\n", db_strerror(ret));

memset(&key, 0, sizeof(DBT));
memset(&data, 0, sizeof(DBT));

key.data = &money;
key.size = sizeof(float);
data.data = description;
data.size = strlen(description) +1;

ret = dbp->put(dbp, NULL, &key, &data, DB_NOOVERWRITE);

if (ret != 0)
fprintf(stderr, "put failed: %s\n", db_strerror(ret));

if (dbp != NULL) dbp->close(dbp, 0);
}

readDb.c:
#include <stdio.h>
#include <string.h>
#include <db.h>

int main(int argc, char *argv[]) {
DBT key, data;
DB *dbp; /* DB structure handle */
int ret; /* function return value */

char *description;
float money = 122.45;

ret = db_create(&dbp, NULL, 0);

ret = dbp->open(dbp, NULL, "my_db.db",
NULL, DB_BTREE, DB_RDONLY, 0);
if (ret != 0)
fprintf(stderr, "open failed: %s\n", db_strerror(ret));

memset(&key, 0, sizeof(DBT));
memset(&data, 0, sizeof(DBT));

key.data = &money;
key.ulen = sizeof(float);
key.flags = DB_DBT_USERMEM;

ret = dbp->get(dbp, NULL, &key, &data, 0);
if (ret != 0)
fprintf(stderr, "get failed: %s\n", db_strerror(ret));

description = (char *)data.data;

printf("Money = %.2f Description = %s\n", money, description);

if (dbp != NULL) dbp->close(dbp, 0);
}

Hi Steve,

There's a bug in the Getting Started Guide -- the "get" code should set
up the key like this:

key.data = &money;
key.size = key.ulen = sizeof(float);
key.flags = DB_DBT_USERMEM;

Otherwise, it looks like a zero-length key to Berkeley DB.

Regards,
Michael.