Where is row_id column definition in magento module-sales-rule module source code?

I looks at salesrule table source code in Magento 2.3.3 vendor/magento/module-sales-rule/etc/db_schema.xml. In that file, it said the table primary key is rule_id column but actually the primary key is row_id. However, I cannot find any row_id text in that module. Where is row_id definition in salesrule table?