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This article introduces you what database standardization skills are, the content is very detailed, interested friends can refer to, hope to be helpful to you.

What are the skills of database standardization

Before you design a table, you should be clear about what you intend to do with the data and how the data will change over time. The assumptions you make will affect the final design.

What kind of data do you need?

When designing an application, it is critical to understand the end result of the design to ensure that you have all the necessary data and know where it comes from. For example, the appearance of the report, the source of each data, and whether all the required data exists. The greatest loss to the project is to find the lack of data in important reports at the later stage of the project.

Once you know what kind of data you need, you must determine the source of the data. Is the data imported from other data sources? Does the data need to be cleaned or validated? Does the user need to enter data?

Identifying the type and source of the required data is the first step in database design.

What are you going to do with the data?

Does the user need to edit this data? If necessary, how should the data be displayed so that users can understand and edit it? Are there any validation rules and related lookup tables? Are there any audit issues associated with data entry that requires editing and deleting reserved backups? What summary information needs to be displayed for the user? Do you need to generate an export file? Once you know this information, you can imagine how fields relate to each other.

How do data relate to each other?

Put the data packets into relevant fields (such as customer-related information, invoice-related information, and so on), and each field group represents the table to be created. Then consider how to relate these tables to each other. For example, which tables have an one-to-many relationship (for example, a customer may hold multiple invoices)? Which tables have an one-to-one relationship (in this case, it is usually considered to combine them into one table)?

How does the data change over time?

After designing a table, serious problems often occur in the future due to the failure to consider the impact of time. Many table designs work very well at the time, but they often crash because users modify data, add data, and over time. Developers often find that the structure of the table needs to be redesigned to accommodate these changes. When the structure of the table changes, all relevant content (queries, forms, reports, code, and so on) must be updated accordingly. Understanding and predicting how the data will change over time can achieve better design and reduce the occurrence of problems.

Learn how to use queries

It is also important to understand how to analyze and manage data. You should have a deep understanding of how queries work, how to use queries to link data between multiple tables, how to use queries to group and summarize data, and how to use crosstab queries when you do not need to display data in a standardized format.

The ultimate goal of good data design is to balance two needs: to store data effectively over time, and to easily retrieve and analyze data. Understanding the function of the query is very helpful in designing the table correctly.

What are the skills of database standardization

The concept of database normalization

This part introduces the basic concepts involved in database standardization, rather than a theoretical discussion on database standardization. How to apply these concepts in your actual situation may vary depending on the needs of your application. The purpose of this section is to understand these basic concepts, apply them according to practical needs, and understand what problems will arise when deviating from these concepts.

Store unique information in one place

Most database developers understand the basic concepts of database normalization. Ideally, you want to store the same data in the same place and use ID to reference when you need it. Therefore, if some information changes, it can be changed in one place, and the corresponding information in the entire program will be changed accordingly.

For example, the customer table stores records for each customer, including name, address, phone number, e-mail address, and other characteristic information. The customer table may contain a unique CustomerID field (usually the Autonumber field), which is the primary key field of the table, which is used by other tables to reference the customer. Therefore, the invoice table can refer only to the customer's ID value, rather than storing all the customer's information in each invoice (because the same customer may hold multiple invoices), so that the customer's ID value can be used to find the customer's details from the customer table. Using powerful forms in Access (using combo boxes and sub-forms), you can do this easily. If you need to modify customer information (such as adding a new phone number), you only need to modify it in the customer table, and any other parts of the application that reference that information will be automatically updated.

With a correctly normalized database, you can easily handle changes in data over time through simple editing. Using a database that is not properly normalized usually requires programming or queries to change multiple records or tables. This not only increases the workload, but also increases the likelihood of data inconsistencies due to incorrect execution of code or queries.

What are the database standardization skills 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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