在 ActiveRecord 中执行后回滚
Rollback after Execute in ActiveRecord
我正在 Rails 中为 sqlite3 数据库构建一个沙箱，以便人们可以自己查询数据。现在我只是像这样调用执行：
@results = ActiveRecord::Base.connection.execute(params[:query])
在破坏性命令的情况下，我想在每次得到结果后回滚。这样做的好方法是什么？
这里我为你准备了一些：
Active Record class ActiveRecord::Base has method called connection()
which returns valid connection to MySQL (or some other) database using
config/database.yml database settings.
Return value of connection() method is an object of class MysqlAdpater
(or [some-other-database]Adapter). Here are some useful methods of
that object:
- execute - executes SQL query. For "SELECT ..." query will return Mysql::Result class (or other result-set class for your Ruby
database interface).
- insert - executes SQL query and returns last inserted id
- update, delete - executes SQL query and returns number of affected rows
- begin_db_transaction - executes SQL query 'BEGIN' (transaction start)
- commit_db_transaction - executes SQL query 'COMMIT' (confirm transaction)
- rollback_db_transaction - executes SQL query 'ROLLBACK' (rollback transaction)
There is also methods select_all and select_one, but we do not
recommend using it, because of inefficient implementation trying to
fetch all selected values to memory.
看看这个 Documentation。
我正在 Rails 中为 sqlite3 数据库构建一个沙箱，以便人们可以自己查询数据。现在我只是像这样调用执行：
@results = ActiveRecord::Base.connection.execute(params[:query])
在破坏性命令的情况下，我想在每次得到结果后回滚。这样做的好方法是什么？
这里我为你准备了一些：
Active Record class ActiveRecord::Base has method called connection() which returns valid connection to MySQL (or some other) database using config/database.yml database settings.
Return value of connection() method is an object of class MysqlAdpater (or [some-other-database]Adapter). Here are some useful methods of that object:
- execute - executes SQL query. For "SELECT ..." query will return Mysql::Result class (or other result-set class for your Ruby database interface).
- insert - executes SQL query and returns last inserted id
- update, delete - executes SQL query and returns number of affected rows
- begin_db_transaction - executes SQL query 'BEGIN' (transaction start)
- commit_db_transaction - executes SQL query 'COMMIT' (confirm transaction)
- rollback_db_transaction - executes SQL query 'ROLLBACK' (rollback transaction)
There is also methods select_all and select_one, but we do not recommend using it, because of inefficient implementation trying to fetch all selected values to memory.
看看这个 Documentation。