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/*
Scan through 10 million records in a pre-built database,
counting all these records which have integer 123 as the value of the third field.
Database was created earlier by speed10. Do not forget to delete database later,
a la: wgdb 10 free
real 0m0.201s
user 0m0.157s
sys 0m0.044s
*/
#include <whitedb/dbapi.h>
#include <stdlib.h>
#include <stdio.h>
int main(int argc, char **argv) {
void *db, *rec;
char *name="10";
int i=0;
int count=0;
wg_int encval;
db = wg_attach_database(name, 1000000000);
if (!db) { printf("db attaching failed \n"); exit(0); }
encval=wg_encode_int(db,123); // encode for faster comparison in the loop
rec=wg_get_first_record(db);
do {
//if (wg_decode_int(db,wg_get_field(db,rec,3))==123) count++; // a bit slower alternative
if (wg_get_field(db,rec,3)==encval) count++;
rec=wg_get_next_record(db,rec);
i++;
} while(rec!=NULL);
wg_free_encoded(db,encval); // have to free encval since we did not store it to db
printf("i %d, count %d\n", i,count);
return 0;
}
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