As a fan of svelte sql backups I've successfully used, for several years this bash script for backing up my Drupal site's databases. By excluding "noisy" tables, I've seen remarkable reduction in the size of the resulting sql file. I am so confident of it, I nearly used it for my Drupal 8 project. However, I presume the schema has undergone some rather significant changes.
Here are the following tables my current script excludes, expressed as a grep pattern:
echo "Starting to dump the table data."
TABLES2=`echo "$TABLES" | grep -Ev "^(accesslog|cache.*|flood|search_.*|semaphore|sessions|feeds_log|watchdog)$"`
mysqldump --complete-insert --disable-keys --single-transaction --no-create-info -u ${USER} --password=${PASS} -h ${HOST} ${DB} ${TABLES2} >> ${DB}.${DATE}.sql
I'm curious how Drupal 8 changes which tables are safe for exclusion. Note that I'd rather err on the "safe" side. So, for example, sessions (as I understand them in D7) have limited value for backup, but that's for my general application. Your mileage may vary. Also, sorry for the unresponsive table, but there is apparently a row length limit on code posts.
| table name: | backup? | | table name: | backup? |
| batch | Yes | | node__comment | Yes |
| block_content | Yes | | node__field_image | Yes |
| block_content__body | Yes | | node__field_tags | Yes |
| block_content_field_data | Yes | | node_access | Yes |
| block_content_field_revision | Yes | | node_field_data | Yes |
| block_content_revision | Yes | | node_field_revision | Yes |
| block_content_revision__body | Yes | | node_revision | Yes |
| cache_bootstrap | No | | node_revision__body | Yes |
| cache_config | No | | node_revision__comment | Yes |
| cache_container | No | | node_revision__field_image | Yes |
| cache_data | No | | node_revision__field_tags | Yes |
| cache_default | No | | queue | Yes |
| cache_discovery | No | | router | Yes |
| cache_dynamic_page_cache | No | | search_dataset | Yes |
| cache_entity | No | | search_index | Yes |
| cache_menu | No | | search_total | Yes |
| cache_render | No | | semaphore | Yes |
| cache_toolbar | No | | sequences | Yes |
| cachetags | No | | sessions | Yes |
| comment | Yes | | shortcut | Yes |
| comment__comment_body | Yes | | shortcut_field_data | Yes |
| comment_entity_statistics | Yes | | shortcut_set_users | Yes |
| comment_field_data | Yes | | taxonomy_index | Yes |
| config | Yes | | taxonomy_term_data | Yes |
| file_managed | Yes | | taxonomy_term_field_data | Yes |
| file_usage | Yes | | taxonomy_term_hierarchy | Yes |
| flood | Yes | | url_alias | Yes |
| history | Yes | | user__roles | Yes |
| key_value | Yes | | user__user_picture | Yes |
| key_value_expire | Yes | | users | Yes |
| menu_link_content | Yes | | users_data | Yes |
| menu_link_content_data | Yes | | users_field_data | Yes |
| menu_tree | Yes | | watchdog | No |
| node | Yes |
| node__body | Yes |
