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/*
creating a flat pointer list of 10 million records of 5 fields in
a 1 GB database:
store a pointer to the previous record to field 3 of each record,
store a pointer to the last record to field 2 of first record.
Observe that we use standard C int 0 for the NULL pointer,
this is also what wg_encode_null(db,0) always gives.
real 0m0.666s
user 0m0.516s
sys 0m0.150s
*/
#include <whitedb/dbapi.h>
#include <stdlib.h>
#include <stdio.h>
int main(int argc, char **argv) {
void *db, *rec, *firstrec, *lastrec;
char *name="15";
int i;
db = wg_attach_database(name, 1000000000);
if (!db) { printf("db creation failed \n"); exit(0); }
rec = wg_create_raw_record(db, 5);
firstrec=rec; // store for use in the end
lastrec=rec;
for(i=1;i<10000000;i++) {
rec = wg_create_raw_record(db, 5);
if (!rec) { printf("record creation failed \n"); exit(0); }
// store a pointer to the previously built record
wg_set_new_field(db,rec,3,wg_encode_record(db,lastrec));
lastrec=rec;
}
// field 3 of the first record will be an encoded NULL pointer
// which is always just (wg_int)0
wg_set_new_field(db,firstrec,3,wg_encode_null(db,0));
// field 2 of the first record will be a pointer to the last record
wg_set_new_field(db,firstrec,2,wg_encode_record(db,lastrec));
printf("i %d\n", i);
wg_detach_database(db);
return 0;
}
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