MDEV-33627 : Implement option --dir in mariadb-import

With that, it is possible to restore the full "instance" from a backup made with mariadb-dump --dir The patch implements executing DDL (tables, views, triggers) using statements that are stored in .sql file, created by mariadb-dump --dir . Care is taken of creating triggers correctly after the data is loaded, disabling foreign keys and unique key checks etc. The files are loaded in descending order by datafile size - to ensure better work distribution when running with --parallel option. In addition to --dir option, following options are implemented for partial restore include-only options: --database - import one or several databases --table - import one or several tables exclude options: --ignore-database -. ignore one or several databases when importing --ignore-table - to ignore one or several tables when importing All options above are only valid together with --dir option, and can be specified multiple times.

Author: vaintroub

client/client_priv.h

@@ -73,6 +73,7 @@ enum options_client
  OPT_DO_SERVER_IDS,
  OPT_SSL_FP, OPT_SSL_FPLIST,
  OPT_UPDATE_HISTORY,
+ OPT_DATABASE,
  OPT_MAX_CLIENT_OPTION /* should be always the last */
 };