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#include <mongoc.h>
#include <stdio.h>
static void
print_pipeline (mongoc_collection_t *collection)
{
mongoc_cursor_t *cursor;
bson_error_t error;
const bson_t *doc;
bson_t *pipeline;
char *str;
pipeline = BCON_NEW ("pipeline", "[",
"{", "$group", "{", "_id", "$state", "total_pop", "{", "$sum", "$pop", "}", "}", "}",
"{", "$match", "{", "total_pop", "{", "$gte", BCON_INT32 (10000000), "}", "}", "}",
"]");
cursor = mongoc_collection_aggregate (collection, MONGOC_QUERY_NONE, pipeline, NULL, NULL);
while (mongoc_cursor_next (cursor, &doc)) {
str = bson_as_json (doc, NULL);
printf ("%s\n", str);
bson_free (str);
}
if (mongoc_cursor_error (cursor, &error)) {
fprintf (stderr, "Cursor Failure: %s\n", error.message);
}
mongoc_cursor_destroy (cursor);
bson_destroy (pipeline);
}
int
main (int argc,
char *argv[])
{
mongoc_client_t *client;
mongoc_collection_t *collection;
mongoc_init ();
client = mongoc_client_new ("mongodb://localhost:27017");
collection = mongoc_client_get_collection (client, "test", "zipcodes");
print_pipeline (collection);
mongoc_collection_destroy (collection);
mongoc_client_destroy (client);
mongoc_cleanup ();
return 0;
}
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