MySQL Learning notes 02-Database overview and MySQL Introduction

mysql| Notes | data | database
Databases are closely linked to everyday applications, and people process various kinds of information by hand, before the database is present. When the information required to record processing is very long, manual processing efficiency appears to be low. For example, patients to hospital for medical treatment, need to pass registration, medical treatment, buy medicine, hospitalization, therapy, rehabilitation and a series of procedures. Registration is to register the patient's name, sex, age and so on. When you buy medicine, the hospital according to prescription from thousands of drugs to pick out the requirements of the drug, need to know the name of the drug, specific location, inventory, how much, and so on. If the patient is many, the hospital chooses the medicine to be very troublesome. If handled manually, the workload is large and it is possible to take the wrong medicine. At this time if through the database processing, simply enter the name of the drug can immediately know the specific location, inventory and how many details. This is not very convenient, improve efficiency, and also avoid the wrong medicine.















The superiority of database (db) only in the organization and management of the information is very large or complex, with manual processing is extremely heavy to display. Of course, large companies that handle millions of of businesses a day can use databases. However, even small companies that have a single person who is interested in maintaining information may need a database. It's not hard to imagine that using a database can have more benefits if the following conditions are present:















Your company has hundreds of employees. Each employee's personal and payroll records need to be kept in order to know who paid the salary and when to pay, and the records must be aggregated so that the revenue statement can be reported to the tax department. It is also important to understand the work that your company hires and the arrangements you make for each job.















You are a teacher and need to know the credits and attendance. Every time you take a quiz or an exam, you record the students ' credits. It is easy to write the exam results in the credit book, but it is very troublesome to use this credit book in the future, it needs a page to search. Even it is not easy to count every student's lack of truancy.















Typically we use a database management system to handle tasks such as those that people use in a file cabinet. Indeed, in a sense, a database is like a large file cabinet, but a built-in file-editing system. Electronic processing records have many advantages over manual processing of records. For example, if you work in some kind of office facility that has a customer record, the database management system can help you in some ways:















Reduce the record filing time. You don't have to look up all the drawers in the cupboard to find the location to add new records. Just place the record in the file orchestration system and make the file orchestration system put the record in the right place for you.















Reduce record retrieval time. When you look up records, you don't have to look up each record to find the record that contains the information you need. If you work in a dental clinic. If you want to send reminders to all patients who have not been diagnosed recently, just ask the file orchestration system to find the right records. Of course, this would be different from telling others to do it. Ask someone else to do it, you just say, "Please make sure which patients have not been here in the last 6 months." ”















Database application system mainly includes databases (database, abbreviation DB), database management system (Data-base Management system, abbreviation DBMS), database application 3. The relationship between these 3 parts is shown in Figure 2.1.









The actual database can be quite complex, and the operation of the database is more complex. I've been more effective in managing and manipulating databases, people have developed database management systems (DB Management system, abbreviated DBMS). DBMS is a software product that people use to manipulate databases. We normally say database Oracle, MS SQL Server, MySQL, Sybase, FoxPro, Access, and so on, all belong to the DBMS category. Although the functionality of these DBMS products varies, the basic functionality is similar to the same.















MySQL is now popular in the relational database of one of them, compared to other database management system (DBMS), MySQL has a small, full-featured, quick query and other advantages, the key is that it is free, can be downloaded free of charge on the Internet, and can be used for free, for the general small and Medium, Even large applications are capable.















The official website of MySQL is: http://www.mysql.com. Many technical support sites, generally if you encounter problems in the learning process, you can go to the following sites to seek support:















http://www.linuxforum.net/















http://www.csdn.com/















Http://tech.ccidnet.com/pub/column/c1108.html















And most importantly, don't forget the following:















http://www.google.com/















http://www.baidu.com/























(Note: Reprint and quote, please indicate author Saulzy)