"Interpersonal relationships" in Databases"

Everything comes from personal imagination. Maybe I am too emotional and too sensitive to things.

It is rational to say that after many database tables are created, a primary key and a foreign key need to be created. Each table has many connections. After the relationship is established, it is like a spider's network, and the disorder is organized. The same is true in our lives. When everyone comes to this world, there are various relationships, and as we grow older, our relationships are expanding as we do in databases. The database has constraints to maintain data integrity. Our relationship networks also need to be restrained. We can make a slight temper to our good friends, but we cannot lose temper to our teachers. This is also a constraint. Beyond this constraint, our relationships are like spider web weaving a hole and trying to make up for it. When we delete or modify fields in a database, the constraints in other tables are involved, and interpersonal relationships are the same, when you target a person, it also affects people with close relationships. Data redundancy is often produced in databases, and some data that we do not use wastes disk space and affects query speed. This is also true in our lives. When we make friends, we will inevitably make friends who don't want to make friends, but we can't help but make friends with them because some places depend on him, it can be understood that such a friend is a friend of redundancy. In the database, the solution is to create another code table and write only the code in the master table, which reduces data redundancy. How can we establish such redundancy in interpersonal relationships? You may also think about it.

Here I want to tell you a story: A bird flew south to spend the winter. It's very cold, and birds are almost frozen. So, fly to a large open space, a cow passes there, pulled a pile of cow dung on the bird's body, frozen bird lying in the dung pile, feel very warm, gradually woke up, it lay warm and comfortable, and soon sang a song. A passing wild cat heard the sound and walked over to see whether it was. Following the sound, the wild cat soon found the bird lying in the dung pile, drag it out and eat it. -- Not everyone who pulls dung from you is your enemy. Not everyone who pulls you out of the dung pile is your friend. Also, when you lie in the dung pile, you 'd better close your mouth.

In terms of sensibility, data is closely related to people, and data is also human data. A good grasp of database applications will go through three realms. 'The West Wind withered green trees last night, tall buildings on its own, and the sky is the greatest path', the first place. 'The clothing is getting wider and the end does not regret it, it's easy for Iraq. 'This second stage is also true. 'Look for him in the crowd, then look back, but the man is in the dark, the lights are dim ', the third environment is also. The realm of improving your thinking is that people and data are combined into one.

A database without constraints is not a good database. A database without constraints is not a good person. A relational database is easy to do and a good database is difficult to do. A relational database can be deleted and reused, but only once in life. This is how data and people interact, but there is another gap between them.

　

Source: http://xiaogang522.blog.ccidnet.com/blog/ccid/do_showone/tid_78654.html