The Algorithm to Check the Correct of Practicing SQL DML

Database query and update statements are the basic experimental content of the database learner, and they are also the very important technology to master the database. But the traditional way to check the correctness of learners' practice is artificial which is not suitable for network environment especially MOOC. The algorithm of static CRC comparison reduces the time spending on searching string of the algorithm of result set comparison. The algorithm of dynamic CRC comparison lowers the time complexity, simultaneously can judge the semantic correctness of query expression written by the learners. We use the operation of rollback and explicit transaction to hold the state of the experiment database to check Insert-Delete-Update operations. We apply some of these algorithms to help learners enhancing their learning efficiency and assisting teacher's teaching.