To create indexes on a MongoDB collection, use mongoc_collection_create_indexes_with_opts():
// `keys`
represents an ascending index on field `x`.
bson_t *keys = BCON_NEW ("x", BCON_INT32 (1));
mongoc_index_model_t *im = mongoc_index_model_new (keys,
NULL /* opts */);
if (mongoc_collection_create_indexes_with_opts (coll,
&im, 1, NULL /* opts */, NULL /* reply */, &error))
{
printf ("Successfully created index\n");
} else {
bson_destroy (keys);
HANDLE_ERROR ("Failed to create index: %s",
error.message);
}
bson_destroy (keys);
To list indexes, use mongoc_collection_find_indexes_with_opts():
mongoc_cursor_t
*cursor = mongoc_collection_find_indexes_with_opts (coll,
NULL /* opts */);
printf ("Listing indexes:\n");
const bson_t *got;
while (mongoc_cursor_next (cursor, &got)) {
char *got_str = bson_as_canonical_extended_json (got, NULL);
printf (" %s\n", got_str);
bson_free (got_str);
}
if (mongoc_cursor_error (cursor, &error)) {
mongoc_cursor_destroy (cursor);
HANDLE_ERROR ("Failed to list indexes: %s",
error.message);
}
mongoc_cursor_destroy (cursor);
To drop an index, use mongoc_collection_drop_index_with_opts(). The index name may be obtained from the keys document with mongoc_collection_keys_to_index_string():
bson_t *keys =
BCON_NEW ("x", BCON_INT32 (1));
char *index_name = mongoc_collection_keys_to_index_string
(keys);
if (mongoc_collection_drop_index_with_opts (coll,
index_name, NULL /* opts */, &error)) {
printf ("Successfully dropped index\n");
} else {
bson_free (index_name);
bson_destroy (keys);
HANDLE_ERROR ("Failed to drop index: %s",
error.message);
}
bson_free (index_name);
bson_destroy (keys);
For a full example, see example−manage−collection−indexes.c.
To create an Atlas Search Index, use the createSearchIndexes command:
bson_t cmd;
// Create command.
{
char *cmd_str = bson_strdup_printf (
BSON_STR ({
"createSearchIndexes" : "%s",
"indexes" : [ {"definition" :
{"mappings" : {"dynamic" : false}},
"name" : "test−index"} ]
}),
collname);
ASSERT (bson_init_from_json (&cmd, cmd_str, −1,
&error));
bson_free (cmd_str);
}
if (!mongoc_collection_command_simple (coll, &cmd, NULL
/* read_prefs */, NULL /* reply */, &error)) {
bson_destroy (&cmd);
HANDLE_ERROR ("Failed to run createSearchIndexes:
%s", error.message);
}
printf ("Created index:
\"test−index\"\n");
bson_destroy (&cmd);
To list Atlas Search Indexes, use the $listSearchIndexes aggregation stage:
const char
*pipeline_str = BSON_STR ({"pipeline" : [
{"$listSearchIndexes" : {}} ]});
bson_t pipeline;
ASSERT (bson_init_from_json (&pipeline, pipeline_str,
−1, &error));
mongoc_cursor_t *cursor =
mongoc_collection_aggregate (coll, MONGOC_QUERY_NONE,
&pipeline, NULL /* opts */, NULL /* read_prefs */);
printf ("Listing indexes:\n");
const bson_t *got;
while (mongoc_cursor_next (cursor, &got)) {
char *got_str = bson_as_canonical_extended_json (got, NULL);
printf (" %s\n", got_str);
bson_free (got_str);
}
if (mongoc_cursor_error (cursor, &error)) {
bson_destroy (&pipeline);
mongoc_cursor_destroy (cursor);
HANDLE_ERROR ("Failed to run $listSearchIndexes:
%s", error.message);
}
bson_destroy (&pipeline);
mongoc_cursor_destroy (cursor);
To update an Atlas Search Index, use the updateSearchIndex command:
bson_t cmd;
// Create command.
{
char *cmd_str = bson_strdup_printf (
BSON_STR (
{"updateSearchIndex" : "%s",
"definition" : {"mappings" :
{"dynamic" : true}}, "name" :
"test−index"}),
collname);
ASSERT (bson_init_from_json (&cmd, cmd_str, −1,
&error));
bson_free (cmd_str);
}
if (!mongoc_collection_command_simple (coll, &cmd, NULL
/* read_prefs */, NULL /* reply */, &error)) {
bson_destroy (&cmd);
HANDLE_ERROR ("Failed to run updateSearchIndex:
%s", error.message);
}
printf ("Updated index:
\"test−index\"\n");
bson_destroy (&cmd);
To drop an Atlas Search Index, use the dropSearchIndex command:
bson_t cmd;
// Create command.
{
char *cmd_str = bson_strdup_printf (BSON_STR
({"dropSearchIndex" : "%s",
"name" : "test−index"}),
collname);
ASSERT (bson_init_from_json (&cmd, cmd_str, −1,
&error));
bson_free (cmd_str);
}
if (!mongoc_collection_command_simple (coll, &cmd, NULL
/* read_prefs */, NULL /* reply */, &error)) {
bson_destroy (&cmd);
HANDLE_ERROR ("Failed to run dropSearchIndex: %s",
error.message);
}
printf ("Dropped index:
\"test−index\"\n");
bson_destroy (&cmd);
For a full example, see example−manage−search−indexes.c.
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