I know a solution was posted for this in magento 1: Clearing Magento after testing
I altered this to work for M2 tables, are there any tables I am missing?
Magento 2 SQL
SET FOREIGN_KEY_CHECKS=0;
-- reset customers
TRUNCATE customer_address_entity;
TRUNCATE customer_address_entity_datetime;
TRUNCATE customer_address_entity_decimal;
TRUNCATE customer_address_entity_int;
TRUNCATE customer_address_entity_text;
TRUNCATE customer_address_entity_varchar;
TRUNCATE customer_entity;
TRUNCATE customer_entity_datetime;
TRUNCATE customer_entity_decimal;
TRUNCATE customer_entity_int;
TRUNCATE customer_entity_text;
TRUNCATE customer_entity_varchar;
ALTER TABLE customer_address_entity AUTO_INCREMENT=1;
ALTER TABLE customer_address_entity_datetime AUTO_INCREMENT=1;
ALTER TABLE customer_address_entity_decimal AUTO_INCREMENT=1;
ALTER TABLE customer_address_entity_int AUTO_INCREMENT=1;
ALTER TABLE customer_address_entity_text AUTO_INCREMENT=1;
ALTER TABLE customer_address_entity_varchar AUTO_INCREMENT=1;
ALTER TABLE customer_entity AUTO_INCREMENT=1;
ALTER TABLE customer_entity_datetime AUTO_INCREMENT=1;
ALTER TABLE customer_entity_decimal AUTO_INCREMENT=1;
ALTER TABLE customer_entity_int AUTO_INCREMENT=1;
ALTER TABLE customer_entity_text AUTO_INCREMENT=1;
ALTER TABLE customer_entity_varchar AUTO_INCREMENT=1;
SET FOREIGN_KEY_CHECKS=1;
SET FOREIGN_KEY_CHECKS=0;
TRUNCATE `sales_creditmemo`;
TRUNCATE `sales_creditmemo_comment`;
TRUNCATE `sales_creditmemo_grid`;
TRUNCATE `sales_creditmemo_item`;
TRUNCATE `sales_invoice`;
TRUNCATE `sales_invoice_comment`;
TRUNCATE `sales_invoice_grid`;
TRUNCATE `sales_invoice_item`;
TRUNCATE `sales_order`;
TRUNCATE `sales_order_address`;
TRUNCATE `sales_order_grid`;
TRUNCATE `sales_order_item`;
TRUNCATE `sales_order_payment`;
TRUNCATE `sales_order_status_history`;
TRUNCATE `sales_shipment`;
TRUNCATE `sales_shipment_comment`;
TRUNCATE `sales_shipment_grid`;
TRUNCATE `sales_shipment_item`;
TRUNCATE `sales_shipment_track`;
TRUNCATE `sales_invoiced_aggregated`;
TRUNCATE `sales_invoiced_aggregated_order`;
TRUNCATE `sales_payment_transaction`;
TRUNCATE `sales_order_aggregated_created`;
TRUNCATE `sales_order_tax`;
TRUNCATE `sales_order_tax_item`;
TRUNCATE `sendfriend_log`;
TRUNCATE `wishlist`;
TRUNCATE `report_event`;
ALTER TABLE `sales_creditmemo` AUTO_INCREMENT=1;
ALTER TABLE `sales_creditmemo_comment` AUTO_INCREMENT=1;
ALTER TABLE `sales_creditmemo_grid` AUTO_INCREMENT=1;
ALTER TABLE `sales_creditmemo_item` AUTO_INCREMENT=1;
ALTER TABLE `sales_invoice` AUTO_INCREMENT=1;
ALTER TABLE `sales_invoice_comment` AUTO_INCREMENT=1;
ALTER TABLE `sales_invoice_grid` AUTO_INCREMENT=1;
ALTER TABLE `sales_invoice_item` AUTO_INCREMENT=1;
ALTER TABLE `sales_order` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_address` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_grid` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_item` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_payment` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_status_history` AUTO_INCREMENT=1;
ALTER TABLE `sales_shipment` AUTO_INCREMENT=1;
ALTER TABLE `sales_shipment_comment` AUTO_INCREMENT=1;
ALTER TABLE `sales_shipment_grid` AUTO_INCREMENT=1;
ALTER TABLE `sales_shipment_item` AUTO_INCREMENT=1;
ALTER TABLE `sales_shipment_track` AUTO_INCREMENT=1;
ALTER TABLE `sales_invoiced_aggregated` AUTO_INCREMENT=1;
ALTER TABLE `sales_invoiced_aggregated_order` AUTO_INCREMENT=1;
ALTER TABLE `sales_payment_transaction` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_aggregated_created` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_tax` AUTO_INCREMENT=1;
ALTER TABLE `sales_order_tax_item` AUTO_INCREMENT=1;
ALTER TABLE `sendfriend_log` AUTO_INCREMENT=1;
ALTER TABLE `wishlist` AUTO_INCREMENT=1;
ALTER TABLE `report_event` AUTO_INCREMENT=1;
SET FOREIGN_KEY_CHECKS=1;
Note:
I see that a plugin exists that does this for M1, does one exist for M2?