Database Normalization Design: Best Practices in PHP Programming

With the rapid growth of real-time data and the continuous development of applications, database normalization design is becoming more and more important in PHP programming. It can help you optimize data structure, reduce data complexity, improve data processing efficiency, and reduce data Risk of error. To this end, in this article, we will introduce some best practices in PHP programming to help you achieve a normalized database design.

First Normal Form (1NF)

The first normal form refers to setting each field in the data table to an atomic value, that is, ensuring that each cell contains only one value, so that Duplication of data is avoided. In PHP programming, we can use multiple tables to implement 1NF design. Here are some examples:

1.1 Split columns

Consider the following table:

user_id	name	email	address
1	John Doe	john@example.com	123 Main St

#In the table above, the field "Address" contains multiple values. So we can break it down into separate tables like this:

user_id	name	email
1	John Doe	john@example.com

address_id	user_id	address
1	1	123 Main St

The benefit of this is that we eliminate duplicate data and are able to query and update more easily.

1.2 Table split

Consider the following table:

order_id	customer_name	customer_email	product_name	price	quantity	total
1	John Doe	john@example.com	Widget	100	1	100
2	Jane Doe	jane@example.com	Gadget	75	2	150

In the above table, the fields "Customer Name", "Customer Email" and "Product Name" are repeated. So we can break it down into separate tables like this:

##111 1001100##2##customer_id | name

order_id	customer_id	product_id	price	quantity	total
2	2	75	2	150

1 | John Doe

2 | Jane Doe

product_id | name

1 | Widget

2 | Gadget

With this method, we not only eliminate duplicate data, but also make the data With more standardization, similar operations can continue. More standardized data will make it easier for us to query and maintain data.

Second Normal Form (2NF)

The second normal form refers to the separation of non-primary key columns to avoid the occurrence of redundant data. A table that meets the 1NF standard can usually be considered to have 2NF.

Consider the following form:

##user_idname##1 John Doejohn@example.com123 Main StUSANew YorkNY 12345

email	address	country	city	state	zip
							In the above table, the information in "Address" can be split into "Country", "City", "State" and "Zip Code". We can break this down into separate tables like this:

user_id

nameemail address_id1John Doejohn@example.com1address_id countrycitystatezip1USANew YorkNY12345Third Normal Form (3NF)

				With this method, we not only fix the problem of redundant data, but also easily add new addresses.

The third normal form is aimed at the situation where dependencies exist in the data table, by separating data with different dependencies into different tables to achieve data normalization . Here is an example:

user_id

nameemailcitystate1John Doejohn@example.comNew YorkNY

				#In the table above, "City" and "State" are dependent on each other. We can split it into separate tables like this:

user_id

nameemailcity_id1John Doejohn@example.com1##city_idcity_namestate_nameNew YorkNY

		1
	In this way, we can manage city and state data more easily, avoid data duplication, and improve database performance. Summary Through the above introduction, we can see that data normalization design is a very important skill in PHP programming. Through this technique, we can reduce the complexity of duplicate data, optimize the data structure, improve database performance, and avoid the risk of data errors. Through reasonable and standardized design, we can not only query and maintain data easily, but also conduct data analysis and decision-making more conveniently. Therefore, in PHP programming, implementing database normalization design is a best practice, and we should apply it to our applications as much as possible.

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