迁移数据问题

1.当传输数据时出现错误，有没有断点重传功能，是从断点 处接着传输，还是重新覆盖数据。
2.日志功能能否可以更完善一些，比如做个对比表。如：在传一个表的数据时，原表有多少条数据，传了多少数据等？
3.在writer部分presql字段为什么没有实现，如我在presql中写入
"preSql": [
"CREATE TABLE IF NOT EXISTS TenantMember (createdAt datetime, updatedAt datetime, user text, _rperm json, _wperm json, tenant text, objectId text);"
],
这个没有生效。

Start by reading the writer section and tracing how the presql field is parsed and executed. Reproduce the reported CREATE TABLE example, then inspect the transfer error and logging paths to separate the retry, comparison-log, and presql concerns. Done requires a maintainer-confirmed scope and tests or documented behavior for each requested change.

Written by the indexing model from the issue text.