Database learning experience and learning experience

Database learning experience and learning experience
Database learning experience is a new concept for us. Of course, the premise is that before we learn it, the first impression of this course is very abstract, it should be difficult and tiring to learn. In the course of learning this course, I gradually gained a sense of database in the course of understanding the database. The word "Database" is not hard to imagine. It is not as amazing as an outsider. As a computer major student, such terminology or professional knowledge is the most basic. Learning is not as difficult as you think, as long as you can understand in class. Sometimes the knowledge books that the teacher talks about cannot be found. They are also supplementary and important content. Sometimes it is difficult to learn because I didn't hear any knowledge points from the teacher. Therefore, in the course of database, you must be prepared for the course. As the teacher said, such a professional course won't work if you want to press the attack a few days before the test, it must be accumulated over time to achieve good results. Through studying databases, I also understand that all walks of life cannot do without databases, and even a small supermarket cannot do without it. It can be seen that the database course is extensive and will be successful if you can learn it carefully. I learned the database with this belief. The first time I got in touch with databases and the first time I got in touch with SQL languages, although I was a stranger, I could learn from the beginning, even if I had no foundation. At the beginning, it was not very difficult to practice the SQL language. Basically, it was done according to the teacher's steps, and it was very fulfilling. After learning single-table queries and join queries, I found that the more difficult I learned, the more I thought about each question for a long time. In addition, each question basically has more than one answer, therefore, you must find the optimal answer. The deletion, insertion, and modification of the following questions have changed dramatically, and the examples in books cannot satisfy us at all. Fortunately, the teacher has provided us with a large number of courseware, we can consolidate our in-class knowledge, learn content-related knowledge, and better complete assignments assigned by teachers. A complete database system was completed in the modified state, which gave me a lot of reflection. First, all factors, including practical factors, must be taken into account for the completion of a database. Second, it is normal to modify such jobs, so don't get bored with it. Third, a complete database must not have errors, otherwise it will bring unnecessary trouble in real life. Through the study of databases and the completion of big jobs this semester, we are very impulsive to work on projects. However, we know that our ability is limited and we need to learn more. The "Database System and Application" course opened this semester has come to an end. Now, we will summarize its knowledge points and their knowledge and the teaching suggestions for this course. 1. Main knowledge points of the database we first understand the concept of the database from the first chapter introduction, which has several important knowledge points, namely, the database (DB) and database system (DBS) the concept of the database management system (DBMS) and the duties of the database administrator (DBA. This chapter also introduces three stages of database development: manual management, file system, and database system. The second chapter introduces the data model and three-tier database. This chapter requires us to understand the entity-contact method and learn to draw a E-R diagram. In addition, we should master the significance of the conceptual data model and the three traditional data models, as well as the data independence and the three-tier schema structure of the database. Next we will focus on the commonly used relational databases. Includes the data structure and basic terms of the relational data model, integrity constraints of the relational model, and relational algebra. The focus is on the classification and functions of the integrity of the relational model, as well as the integrated operation and relational operation of relational algebra. Finally, the three-tier schema of the relational database system is introduced. Chapter 5 describes the definition, query, operation, and control functions of the standard language SQL of relational databases. The focus is on the data query function. The usage of views and the definition, operation, and query functions in dynamic SQL are also introduced. Chapter 6 knowledge points include: creation and execution of stored procedures, modification and deletion; basic concepts of triggers, creation, insertion and deletion of views, insertion, deletion, and update of class triggers. Finally, we introduce data integrity. Chapter 7 introduces security, including security measures, database management system security functions, user management, role management, and permission management. Other security issues include data encryption, auditing, statistical database, and user-defined security measures. The transaction management chapter first introduces the concept and nature of transactions and SQL support for transactions. Concurrency Control-interference problem, serializability, blocking, deadlock, isolation level, blocking and isolation level; recovery-fault type, Backup Type, log concept, recovery model, backup dump, and restoration. Chapter 9 Relational Data Theory: function dependency terms and symbols; the principle system of Function Dependence-the content and correctness of Amstrong's principle, logical implication and closure, the completeness of the principle, the calculation of the closure, and the equivalence and minimization of the function dependency set; normalization: 1NF, 2NF, 3NF, and BCNF; mode decomposition. Chapter 10: Database Design. Improve the concept of E-R model-weak entity, dependency, forced contact; the process of database design mainly master its establishment steps. Chapter 2 introduces Object-Oriented Databases: new database applications and new database types; Object-oriented Data Models-objects and classes; attributes, methods and states of objects, interaction and message of objects, determination and differentiation of classes, encapsulation, inheritance and Polymorphism of objects, Object Relational Database and object database, and research on object-oriented database. Chapter 12 "database application structure and development environment" is not the focus, and Chapter 4 has been mastered in the software engineering course, so the knowledge points of these two chapters are skipped. Chapter 2 distributed database and distributed data management: concepts; distributed database distribution methods; features and objectives of distributed databases-update propagation, Distributed Query Processing, directory table management, and distributed transaction management; replication of SQL Server, its terms, and the replication model. Chapter 15 data warehouse: concept, structure, data warehouse system, data warehouse system, database model of data warehouse, and data warehouse and decision support. Finally, you can grasp the knowledge of the knowledge base in the new fields of database research and application. 2. Learning about the database SQL (Structured Query Language) is the syntax used to execute queries. However, the SQL language also contains the syntax used to update, insert, and delete records. The query and update commands constitute the DML part of SQL: SELECT-obtain data from database tables UPDATE-UPDATE data in database tables DELETE-DELETE data from database tables insert into-INSERT data SQL data definition language (DDL) to database tables) some enable us to create or Delete tables. We can also define indexes (KEYS), define links between tables, and apply constraints between tables. The most important DDL statement in SQL: CREATE DATABASE-CREATE new DATABASE-modify DATABASE CREATE TABLE-CREATE new TABLE-change (change) database table drop table-delete table create index-create index (search key) drop index-delete INDEX database maintains data independence, data stored in a database exists independently of all applications that process data. That is to say, data is a symbolic identifier of an objective object. It is an objective existence and does not change its structure because of the needs of an application, therefore, it is an objective entity independent of applications. An application processes data to obtain information, that is, an application. It can only design the required data processing methods based on objective data, instead of changing the objective data itself. The traditional definition of a database is a collection of related data stored in an organizational manner, mainly represented as a collection of data tables. According to the standard, SQL statements can be divided into the following six categories based on different functions: Data-Definition Language (DDL); Data-Manipulation Language SQL Server2005 function, DML); Transaction-Management Language (TML); Data-Control Language (DCL); and Data-Query Language (DQL ); cursor control
Statement (Cursor-Control Language, CCL ). There are still a lot of things you don't know about in this course, and you still need to study it later. 3. My personal views on how to learn the database: 1. First, from the perspective of self-study, because the database has a large amount of content, therefore, when teaching, the teacher did not teach every knowledge point in detail to us. Therefore, in general, the connection between the knowledge points was not very strong during the course, this requires us to make preparations before learning this course. Of course, it is necessary to listen carefully during the class. In addition, we need to chew on the content of the class after class, there is also a certain amount of exercises for the corresponding exercises, which should be considered repeatedly for non-questions. Here, you can solve the problem by asking the students or teachers, you cannot leave questions that you don't want to answer. As a result, blind spots accumulate more and more, and ultimately affect your enthusiasm for database learning. The above is a learning method for theoretical knowledge. For the Lab Course of database, the two methods are basically the same. They only use the hands-on course to practice theoretical knowledge. At the same time, it also deepens the understanding of theoretical knowledge. 2. Sometimes, learning is not just an individual's self-closed learning. We cannot understand self-learning as one's own learning, but actually learning, or more efficient learning, it is a kind of team spirit learning, because everyone looks at the problem from different perspectives. Through continuous communication with classmates and teachers, we can have a deeper understanding of something, in this way, we can get twice the result with half the effort, saving us a lot of effort, and the final problem cannot be effectively solved. Therefore, to sum up, learning the database well is beyond the self-study of individuals, we also need to strengthen communication with others, create a good learning atmosphere, and lay the groundwork for learning databases well.
We will learn databases this year and learn databases well.

As an automation professional, database is not learned too deeply as a general knowledge. I don't think it is too difficult to learn databases. the key is to clarify the relationship between fields and between tables. 2. Express the actual relationship with an appropriate table structure.

Learning about databases

Database technology should be the core of computer technology, not only operating systems, but also data storage.
You can participate in a project on your own or perform database operations to improve the learning speed.
Currently, Foxpro is good for small desktop databases, most of which are SQL Server2000 and large Oracle databases.
We recommend that you learn SQL Server2000, which is relatively simple.

Programming is hard to say, simple and simple. If you want to start with something, I think you should first learn the C language. First, you must have a concept about how to program, then you can learn the database and ASSECC or SQL, both of which are simple databases. Later, you will learn HTML and ASP (which can be understood as the two scripting languages VBscript and JAVAscript ), with these languages as the foundation, you can learn something difficult. Learning the object-oriented concept of C ++, when you think of the three main features of object-oriented {Derived classes and inheritance; polymorphism ;... (3rd are somewhat forgotten. It seems like encapsulation, or separation of derivation and inheritance. In short, there are three main features .)} you can understand and use JAVA in your own programming. You may have heard that JAVA and C ++ are simple object-oriented, JAVA is like a combination of C ++ and C. JAVA is basically all object-oriented concepts, but the programming structure in it is: -- loop; judgment is the mechanism of C language.