{% assign diagram_id = include.id | default: 'transaction' %}
What readers see during an update Under READ COMMITTED, start with revision zero. A transaction updates it to one. The writer sees one through a source-table read, while another session still sees zero. After COMMIT, a new statement in the other session sees one. After ROLLBACK, it still sees zero. Committed rowrevision = 0 BEGIN; UPDATE Transaction open Writer reads 1 Other session reads 0 COMMIT ROLLBACK Next readrevision = 1 Next readrevision = 0
READ COMMITTED, starting from revision 0. “Next read” means a new statement in the other session after COMMIT or ROLLBACK. The writer reads its own change through the source table.