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#include <stdio.h>
#include <whitedb/dbapi.h>
int main(int argc, char **argv) {
void *db, *rec;
wg_int enc;
wg_query_arg arglist[2]; /* holds the arguments to the query */
wg_query *query; /* used to fetch the query results */
db = wg_attach_database("1000", 2000000);
/* just in case, create some records for testing */
rec = wg_create_record(db, 10);
enc = wg_encode_int(db, 443); /* will match */
wg_set_field(db, rec, 7, enc);
rec = wg_create_record(db, 10);
enc = wg_encode_int(db, 442);
wg_set_field(db, rec, 7, enc); /* will not match */
/* now find the records that match the condition
* "field 7 equals 443 and field 6 equals NULL". The
* second part is a bit redundant but we're adding it
* to show the use of the argument list.
*/
arglist[0].column = 7;
arglist[0].cond = WG_COND_EQUAL;
arglist[0].value = wg_encode_query_param_int(db, 443);
arglist[1].column = 6;
arglist[1].cond = WG_COND_EQUAL;
arglist[1].value = wg_encode_query_param_null(db, NULL);
query = wg_make_query(db, NULL, 0, arglist, 2);
while((rec = wg_fetch(db, query))) {
printf("Found a record where field 7 is 443 and field 6 is NULL\n");
}
/* Free the memory allocated for the query */
wg_free_query(db, query);
wg_free_query_param(db, arglist[0].value);
wg_free_query_param(db, arglist[1].value);
return 0;
}
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