MySQL - SET 数据类型

要通过 JavaScript 程序创建 SET 数据类型的列，我们需要使用mysql2 库的query()函数执行“CREATE TABLE”语句，如下所示：

sql = "CREATE TABLE test_table (ID INT auto_increment primary key, COL1 set('Goa', 'Assam', 'Delhi', 'Kerala') )";
con.query(sql);

要通过 Java 程序创建 SET 数据类型的列，我们需要使用JDBC 函数execute()执行“CREATE TABLE”语句，如下所示：

String sql = "CREATE TABLE test_table (ID INT auto_increment primary key, COL1 set(\"Goa\", \"Assam\", \"Delhi\", \"Kerala\"))";
statement.execute(sql);

要通过 python 程序创建 SET 数据类型的列，我们需要使用MySQL Connector/Python 的execute()函数执行“CREATE TABLE”语句，如下所示：

sql = 'CREATE TABLE test_table (ID INT AUTO_INCREMENT PRIMARY KEY,  COL1 SET('Goa', 'Assam', 'Delhi', 'Kerala'))'    
cursorObj.execute(sql)

var mysql = require("mysql2");
var con = mysql.createConnection({
   host: "localhost",
   user: "root",
   password: "password",
}); //Connecting to MySQL

con.connect(function (err) {
   if (err) throw err;
   //console.log("Connected successfully...!");
   //console.log("--------------------------");
   sql = "USE TUTORIALS";
   con.query(sql);

   //create a test_table table, that accepts one column of set type.
   sql = "Create table test_table (ID INT auto_increment primary key, COL1 set('Goa', 'Assam', 'Delhi', 'Kerala') )";
   con.query(sql);
   
   //insert data into created table
   sql = "INSERT INTO test_table (COL1) VALUES ('Goa,Assam'), ('Assam,Goa'), ('Goa,Assam,Goa'), ('Goa,Assam,Assam'), ('Assam,Goa,Assam')";
   con.query(sql);
   
   //select datatypes of salary
   sql = `SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE table_name = 'test_table' AND COLUMN_NAME = 'col1'`;
   con.query(sql, function (err, result) {
     if (err) throw err;
     console.log(result);
   });
});  

输出

生成的输出如下：

[ { DATA_TYPE: 'set' } ]

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class Set {
   public static void main(String[] args) {
      String url = "jdbc:mysql://:3306/TUTORIALS";
      String username = "root";
      String password = "password";
      try {
         Class.forName("com.mysql.cj.jdbc.Driver");
         Connection connection = DriverManager.getConnection(url, username, password);
         Statement statement = connection.createStatement();
         System.out.println("Connected successfully...!");

         //Set data types...!;
         String sql = "Create table test_table (ID INT auto_increment primary key, COL1 set(\"Goa\", \"Assam\", \"Delhi\", \"Kerala\"))";
         statement.execute(sql);
         System.out.println("column of a SET type created successfully...!");
         ResultSet resultSet = statement.executeQuery("DESCRIBE test_table");
         while (resultSet.next()){
            System.out.println(resultSet.getString(1)+" "+resultSet.getString(2));
         }
         connection.close();
      } catch (Exception e) {
         System.out.println(e);
      }
   }
}  

输出

获得的输出如下所示：

Connected successfully...!
column of a SET type created successfully...!
ID int
COL1 set('Goa','Assam','Delhi','Kerala')  

import mysql.connector
# Establishing the connection
connection = mysql.connector.connect(
    host='localhost',
    user='root',
    password='password',
    database='tut'
)
# Creating a cursor object
cursorObj = connection.cursor()
# Create table with Set column
sql = '''
CREATE TABLE test_table (
ID INT AUTO_INCREMENT PRIMARY KEY,
COL1 SET('Goa', 'Assam', 'Delhi', 'Kerala')
)
'''
cursorObj.execute(sql)
print("The table is created successfully!")
# Data to be inserted
data_to_insert = [
    ('Goa,Assam',),
    ('Assam,Goa',),
    ('Goa,Assam,Goa',),
    ('Goa,Assam,Assam',),
    ('Assam,Goa,Assam',)
]
# Insert data into the created table
insert_query = "INSERT INTO test_table (COL1) VALUES (%s)"
cursorObj.executemany(insert_query, data_to_insert)
# Commit the changes after the insert operation
connection.commit()
print("Rows inserted successfully.")
# Now display the table records
select_query = "SELECT * FROM test_table"
cursorObj.execute(select_query)
result = cursorObj.fetchall()
print("Test Table Data:")
for row in result:
    print(row)
cursorObj.close()
connection.close()

输出

以下是上述代码的输出：

The table is created successfully!
Rows inserted successfully.
Test Table Data:
(1, {'Assam', 'Goa'})
(2, {'Assam', 'Goa'})
(3, {'Assam', 'Goa'})
(4, {'Assam', 'Goa'})
(5, {'Assam', 'Goa'})