The rows in the data table are called records; the columns in the data table are called fields. A database is a "warehouse that organizes, stores and manages data according to a data structure"; it is a collection of large amounts of data that is stored in a computer for a long time, is organized, shareable and unified management.
The rows in the data table are called records; the columns in the data table are called fields
The database is " A warehouse that organizes, stores, and manages data according to data structures." It is a collection of large amounts of data that is stored in a computer for a long time, is organized, shareable, and unified management.
A database is a collection of data that is stored together in a certain way, can be shared with multiple users, has as little redundancy as possible, and is independent of applications. It can be regarded as an electronic filing cabinet—— A place where electronic files are stored. Users can add, query, update, delete and other operations on the data in the files.
Extended information:
The database management system is the core component of the database system, which mainly completes the manipulation and management functions of the database. , realize the creation of database objects, query, add, modify and delete operations of database stored data, and user management and permission management of the database, etc.
Its security is directly related to the security of the entire database system. Its protection methods mainly include:
(1) Use genuine database management systems and install relevant patches in a timely manner.
(2) Do a good job in user account management, disable the default super administrator account or set a complex password for the super administrator account; allocate dedicated accounts for access to applications; set user login time and login failure limit , to prevent brute force cracking of user passwords.
(3) When allocating user access rights, adhere to the principle of least privilege allocation and restrict users to only access specific databases and cannot access other databases at the same time.
(4) Modify the default access port of the database, use a firewall to block other ports open to the outside world, and prohibit all external port detection behaviors.
(5) Encrypt and store important data and sensitive data stored in the database to prevent data leakage caused by database backup or data file theft.
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