如果以前的数据库与IIS位于同一台计算机上，问题是，对数据库的任何调用现在必须通过网络传输。尽量减少要执行的查询数量，例如使用适当的 JOIN 表在一个查询中查询一个表的记录和另一个表中的相关行，而不是一个表中的记录，后面跟一个查询查询其他表中的详细信息每行的表。

还要检查迁移时是否没有遗漏某些键/索引。

If the previous database was located on the same machine with IIS, the problem is that any call to the database must now travel over the network. Try to minimize the number of queries to be executed, e.g. with appropriate JOINs of tables querying records of one table and dependent rows from another table in one query, instead of records from one table followed by one query for the details in the other table for each row.
Also check that you did not miss some keys / indices when migrating.