sqlite表中的每一行如何唯一？不只是一列

Question

我有一个sqlite表，其中有两列，例如name和surname。我希望name和surname必须不同，而不仅仅是name。

我的表格代码是

private static final String MAKE_TABLE_NAME_SURNAME = "CREATE TABLE " +
 TABLE_DISEASE_SEMPTOM + "(" + KEY_DSID  " INTEGER PRIMARY KEY AUTOINCREMENT," +
 NAME + " TEXT, " + SURNAME + " TEXT) ";

我不能使用

private static final String MAKE_TABLE_NAME_SURNAME = "CREATE TABLE " +
 TABLE_DISEASE_SEMPTOM + "(" + KEY_DSID  " INTEGER PRIMARY KEY AUTOINCREMENT," +
 NAME + " TEXT UNIQUE, " + SURNAME + " TEXT UNIQUE) ";

因为如果我使用此代码，则无法添加相同的名称但不同的姓氏或相同的姓氏但不同的名字。如果只有两个相同，怎么能忽略呢？

Answer 1

此检查在服务器/应用程序一侧进行。 （在尝试将变量插入数据库之前，先检查一下变量）

Answer 2

我相信以下是您想要的：-

private static final String MAKE_TABLE_NAME_SURNAME = "CREATE TABLE " +
   TABLE_DISEASE_SEMPTOM + "(" + KEY_DSID  " INTEGER PRIMARY KEY AUTOINCREMENT," +
   NAME + " TEXT, " + SURNAME + " TEXT, UNIQUE(" + NAME + "," + SURNAME +")) ";

也就是说，您正在定义名称列和姓氏列的组合作为UNIQUE约束。

例如考虑：-

DROP TABLE IF EXISTS TABLE_DISEASE_SEMPTOM;
CREATE TABLE IF NOT EXISTS TABLE_DISEASE_SEMPTOM (KEY_DSID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT, SURNAME TEXT, UNIQUE(NAME,SURNAME));
INSERT INTO TABLE_DISEASE_SEMPTOM (NAME,SURNAME) VALUES('Fred','Bloggs'),('Fred','Smith'),('Mary','Smith'),('Jane','Doe');
INSERT OR IGNORE INTO TABLE_DISEASE_SEMPTOM (NAME,SURNAME) VALUES('Fred','Bloggs'); -- will not be inserted as duplicate
SELECT * FROM TABLE_DISEASE_SEMPTOM;

前四个插入工作，最后一个（靠自己）被忽略（因为它是重复的）。 因此，最终查询产生：-

日志为：-

INSERT INTO TABLE_DISEASE_SEMPTOM (NAME,SURNAME) VALUES('Fred','Bloggs'),('Fred','Smith'),('Mary','Smith'),('Jane','Doe')
> Affected rows: 4
> Time: 0.117s


INSERT OR IGNORE INTO TABLE_DISEASE_SEMPTOM (NAME,SURNAME) VALUES('Fred','Bloggs')
> Affected rows: 0
> Time: 0.117s

即最后一次插入没有插入行