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/** @page tut_mongo_sync_cmd_index_create Creating indexes
*
* This example will show how to properly create indexes, how to
* verify its success, and will also give hints on how to prepare the
* BSON used to create the index.
*
* @dontinclude tut_mongo_sync_cmd_index_create.c
* @until stdio.h
*
* We will be creating and verifying multiple indexes, so lets create
* a function that takes a connection, a prepared index, and does the
* create and verify magic.
*
* @line static void
* @until }
* @until }
*
* This will create the index, and if it succeeds, write that to
* stdout. If it fails, it will try to query the last error, and print
* that to stderr.
*
* All we have to do past this point, is to build a few index
* specifications in BSON, and see what happens:
*
* @line int
* @until bson
*
* @line invalid
* @until bson_finish
*
* The first index spec we create will have a single index field, @a
* name, where we set the value to an empty string. However - as we
* will soon see - this is not a valid specification, as MongoDB does
* not accept string-typed fields in the index spec.
*
* @line index
* @until bson_finish
*
* Armed with the knowledge that strings are not going to work, we
* turn to our trusty old integers. Integers (32-bit integers at that,
* there really is no need to use a 64-bit value here) are the best
* fit for the type of an index field, because one can tell MongoDB
* the sort order (with negative or positive numbers) with them easily.
*
* @line conn =
* @until }
*
* We now have two index specs in BSON, and an established connection,
* lets see what happens!
*
* @line create_and_verify
* @until conn, index
*
* The first will - as explained above - fail, the second will
* succeed.
*
* And that is all it takes to create simple indexes! We now free up
* our BSON objects and disconnect, and the tutorial program is all
* done and finished.
*
* @line bson_free
* @until disconnect
*
* @line return
* @until }
*/
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