6.6 Notes-transactions, views, indexes, backups, recovery databases for the database

a transaction transaction (TRANSACTION) is a series of four characteristics of an operational transaction executed as a single logical unit of work atomic consistency persistence isolation open transaction B Egin;    or START TRANSACTION COMMIT TRANSACTION commit ROLLBACK TRANSACTION rollback MySQL is the default turn on transaction autocommit (Oracle default does not turn on transaction autocommit) Second, view a virtual table    A table can create several different views to create a view for creating views named as Select ... Delete a view name three, index is a valid way to combine data for quick Find specifies the record index type: Normal index, primary key index, unique index, full-text index creation index: Create INDE    X index_student_studentname on student (studentname); rule: frequently searched columns are often used as columns for query selection, often sorted, grouped columns often used as columns for connections (primary key/foreign Key) Cons: Occupy storage space impact data deletion, add and update efficiency view all indexes Iv. backing up and recovering databases mysqldump-uroot-p myschool2>D:\myschool_bk.sql//back up data only, no table statement createdMysqldump-uroot-p-T myschool2>D:\myschool_bk.sql//- c indicates that the INSERT statement has a field nameMysqldump-uroot-p-t-c myschool2>D:\myschool_bk3.sql//-D indicates that only the table structure is backed up and there are no INSERT statementsMysqldump-uroot-p-D myschool2>D:\myschool_bk4.sql

6.6 Notes-transactions, views, indexes, backups, recovery databases for the database