相关研究表明，使用精美逼真的玩具进行游戏，更多地促使儿童（） 模仿。 记忆。 思考。 创造。
Your database operates in ARCHIVELOG mode and all the tablespaces are online. Due to a user error， you decided to perform an incomplete recovery. Which two tasks would you be required to perform in the recovery process？（） open the database with the RESTRICTED option。 open the database with the RESETLOGS option。 recover to the required SCN only that data file in which the error occurred。 recover all the data files to the same system change number （SCN）。
下述试验方法中，属于粒度成分分析的试验是（） 沉降分析法。 标准贯入试验。 搓条法。 原位压缩试验。
旋转件不平衡时，所产生的离心力，其大小与（）、（）以及（）成正比。
In your database， you discovered that a tempfile in a locally managed temporary tablespace has been deleted at the operating system level. How would you recover the tablespace？（） flash back the database。 perform point-in-time recovery。 perform a full database recovery。 drop and re-create the tablespace。 use Recovery Manager （RMAN） to recover the database。
开孔机刀具结合器尾部做成内螺纹的作用是（）
