The duration of this section needs to be controlled 5 Within minutes
1 What is data （Data）
The symbolic record that describes things is called data , The symbols describing things can be numbers , It can also be words 、 picture , Images 、 voice 、 Language, etc. , Data comes in many forms , They can all be digitized and stored in computers
Describe a thing in a computer , We need to extract the typical characteristics of this thing , Make a record , It's like a line in the document , Such as ：
1 egon,male,18,1999, Shandong , Department of Computer Science ,2017,oldboy
A single record doesn't make any sense , If we separate by commas , Define the meaning of each field in turn , Equivalent to defining the title of a table
1 name,sex,age,birth,born_addr,major,entrance_time,school # Field
2 egon,male,18,1999, Shandong , Department of Computer Science ,2017,oldboy # Record
So we can understand egon, Gender is male , Age 18 year , Born in 1999 year , His birthplace is Shandong ,2017 He was admitted to the old boy's computer department
2 What is a database （DataBase, abbreviation DB）
A database is a warehouse for data , It's just that the warehouse is on a computer storage device , And the data is stored in a certain format
People used to store data in file cabinets , Now the amount of data is huge , It's no longer applicable
Database is stored in computer for a long time 、 Organized 、 Data that can be shared .
The data in the database is organized according to a certain data model 、 Describe and store , With less redundancy 、 High data independence and scalability , And can be used for all kinds of User sharing
3 What is database management system （DataBase Management System abbreviation DBMS）
In understanding Data And DB After the concept of , How to organize and store data scientifically , How to acquire and maintain data efficiently becomes the key
This uses a system software — Database management system
Such as MySQL、Oracle、SQLite、Access、MS SQL Server
mysql It is mainly used for large portals , For example, Sogou 、 Sina, etc , Its main advantage is open source , Because the open source database is free , He is now a product of Oracle .
oracle Mainly used in banks 、 The railway 、 Airport, etc . The database is powerful , High software cost . It's also Oracle's product .
sql server It's a Microsoft product , It is mainly used in large and medium-sized enterprises , Like Lenovo 、 Founder et al .
4 database server 、 data management system 、 database 、 The relationship between table and record （ Focus on understanding ！！！）
Record ：1 Liu Hailong 324245234 22（ Information from multiple fields makes up a record , A line in a file ）
surface ：student,scholl,class_list（ I.e. documents ）
database ：oldboy_stu（ It's a folder ）
Database management system ： Such as mysql（ It's a software ）
database server ： A computer （ High memory requirements ）
summary ：
database server -： Run database management software
Database management software ： management - database
database ： It's a folder , Used to organize files / surface
surface ： I.e. documents , Used to store multiple lines of content / Multiple records
