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This article will explain in detail what are the advantages of mysql self-enhancement. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

The selection of "natural key" and "surrogate key" will be entangled in the design of database table, and the implementation of natural key is more complicated when realizing data "soft deletion". Some natural keys are not suitable as table primary key because the key value is too long or the combination of multiple columns, while the two common surrogate keys are self-increment column (auto incremnet) and global unique identification column (GUID). Pick up

In mysql, the self-incrementing field provided by the database is used as the self-incrementing primary key.

Advantages:

(1) the automatic numbering of the database is fast, and it grows incrementally, and it is stored sequentially, which is very beneficial to retrieval.

(2) Digital type, which takes up small space, is easy to sort, and is convenient to transfer in the program.

(3) if you add records through a non-system, you don't have to specify this field and you don't have to worry about duplicate primary keys.

After talking about the advantages and disadvantages, in fact, its disadvantages come from its advantages.

Disadvantages:

(1) because of automatic growth, it will be troublesome to insert the specified ID records manually, especially when the system is integrated with other systems and data import is needed, it is difficult to ensure that the ID of the original system does not have primary key conflicts (provided that the old system is also digital). Especially when the new system is online, the old and new systems exist in parallel, and there are heterogeneous databases, and when two-way synchronization is needed, self-increasing primary keys will be your nightmare.

(2) during system integration or splicing, if the primary keys of the new and old systems are different from each other, the data type of the primary key will be modified, which will also lead to the modification of other tables associated with foreign keys, and the consequences will be equally serious.

(3) if the system is also digital, in order to distinguish between new and old data, you may want to add a character identification (such as "o", old) in front of the old data primary key to indicate that this is the old data, then the automatically growing digital type faces another challenge.

About what the advantages of mysql self-enhancement is to share here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

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