MySQL data type optimization

table of Contents

Selection of data type

int type storage time-time conversion

Create Table

Import Data

Fetch data

IP address storage

Create Table 

Import Data

Convert the result to an IP address

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Selection of data type

1. Use the smallest data type that can save your data. (Time type data: you can use the varchar type, you can use the int type, you can also use the timestamp type)
2. Use a simple data type, int is simpler than varchar type in mysql processing. (Int type storage time is the best choice)
3. Use not null to define fields as much as possible. (Due to the characteristics of innodb, the value of null requires additional storage in the field, and it will also increase the cost of IO and storage.)
4. Try to use the text type as little as possible. It is best to consider the table when it is necessary.

 

 

int type storage time-time conversion

 

Use int to store date and time, and use FROM_UNIXTIME (), UNIX_TIMESTAMP () two functions to convert. 

• unix_timestamp () function is to convert the date format data to int type
• FROM_UNIXTIME (timestr) function is to convert int type to time format

Create Table

create table test(
id int auto_increment not null,
timestr int ,
primary key(id)
);

Import Data

insert into test (timestr) values (unix_timestamp('2018-05-29 16:00:00'));

Fetch data

 

 

IP address storage

 

In our external application, we must record the ip address. In most cases, varchar (15) is used for storage, which requires 15 bytes for storage, but bigint only requires 8 bytes for storage. Use INET_ATON (), INET_NTOA () two functions to convert.

Create Table 

create table sessions(
id int auto_increment not null,
ipaddress bigint,
primary key (id)
);

Import Data

insert into sessions (ipaddress)values (inet_aton('192.168.0.1'));

 

Convert the result to an IP address

select inet_ntoa(ipaddress) from sessions;