java - Mysql无法将具有特定字符的值存储到数据库

Question

我在mysql中的代码:

`SET NAMES 'utf8';`    `SET CHARACTER SET 'utf8';`    `SET COLLATION_CONNECTION = 'utf8_unicode_ci';`    `insert into test (regOznaka) values ("NS 247 SČ"), ("NS 247 SĆ"), ("NS 247 SC");`    

结果是:

Error code 1062, SQL state 23000: Duplicate entry 'NS 247 SĆ' for key 'PRIMARY'

我该如何解决这个问题？

Answer 1

A primary key, also called a primary keyword, is a key in a relational database that is unique for each record. It is a unique identifier, such as a driver license number, telephone number (including area code), or vehicle identification number (VIN). A relational database must always have one and only one primary key.

以下是将 ID 属性定义为 CUSTOMERS 表中主键的语法。

 REATE TABLE CUSTOMERS(
   ID   INT              NOT NULL,
   NAME VARCHAR (20)     NOT NULL,
   AGE  INT              NOT NULL,
   ADDRESS  CHAR (25) ,
   SALARY   DECIMAL (18, 2),       
   PRIMARY KEY (ID)
);

对于您的查询，您应该使用不同于“NS 247 SĆ”的惰性值