SQLite在Android中創建具有多個主鍵的表格

Question

請引導我。如何以這種方式將兩個列定義爲主鍵。

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

感謝

Answer 1

多個主鍵應該另行申報。查詢是以格式問題寫成的。

"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 + "))" 

如果表只有一個，然後

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

Answer 2

你可以試試這個 -

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