SQLite在Android中创建具有多个主键的表格

Question

请引导我。如何以这种方式将两个列定义为主键。

sqLiteDatabase.execSQL("CREATE TABLE IF NOT EXISTS " + TABLE_ATTENDEE + 
         " (" + COLUMN_Att_Event_ID + " TEXT PRIMARY KEY, " + 
         COLUMN_Att_Email + " TEXT PRIMARY KEY)"); 

感谢

Answer 1

多个主键应该另行申报。查询是以格式问题写成的。

"CREATE TABLE IF NOT EXISTS " + TABLE_ATTENDEE + 
" (" + COLUMN_Att_Event_ID + " TEXT," + 
COLUMN_Att_Email + " TEXT, PRIMARY KEY(" + COLUMN_Att_Event_ID + "," + COLUMN_Att_Email + "))" 

如果表只有一个，然后

"CREATE TABLE IF NOT EXISTS " + TABLE_ATTENDEE + 
" (" + COLUMN_Att_Event_ID + " TEXT PRIMARY KEY," + 
COLUMN_Att_Email + " TEXT" 

Answer 2

你可以试试这个 -

CREATE TABLE tablename (
    column1, 
    column2, 
    PRIMARY KEY (column1, column2) 
);