在Android中重置INTEGER PRIMARY KEY AUTOINCREMENT

我创建了一个名为DRINK的表。我最初插入了两行。升级时，我想删除两行并将我的主键重置为1.我得到的行要删除，但没有任何运气重置主键。有人知道如何做到这一点的语法，或者甚至有可能吗？这是从我的onUpdate函数调用的函数：在Android中重置INTEGER PRIMARY KEY AUTOINCREMENT

private void updateMyDatabase(SQLiteDatabase db, int olderVersion, int newVersion){ 
    Log.v("DatabaseHelper","UPDATE MY DATABASE"); 
    if (olderVersion<1){ 
     db.execSQL("CREATE TABLE DRINK (_id INTEGER PRIMARY KEY AUTOINCREMENT," 
       + "NAME TEXT, " 
       + "DESCRIPTION TEXT, " 
       + "IMAGE_RESOURCE_ID INTEGER);"); 
     insertDrink(db,"latte","Espresso and Steamed Milk",R.drawable.latte); 
     insertDrink(db, "cappuccino", "This a Cappuccino", R.drawable.cap); 
    } 
    if (olderVersion < 2){ 
     db.execSQL("delete from DRINK"); 
     db.execSQL("alter table AUTO_INCREMENT =1"); //*** NEED HELP HERE*** 
     insertDrink(db, "coff", "Espresso and Steamed Milk", R.drawable.latte); 
    } 
}

我在网上找到这段代码，但它不工作。谢谢。

db.execSQL("alter table AUTO_INCREMENT =1");

来源

2015-10-18 Mark F

删除行将不会重置ROWID。

SQLite的文档指出：

SQLite keeps track of the largest ROWID that a table has ever held using the special SQLITE_SEQUENCE table. The SQLITE_SEQUENCE table is created and initialized automatically whenever a normal table that contains an AUTOINCREMENT column is created. The content of the SQLITE_SEQUENCE table can be modified using ordinary UPDATE, INSERT, and DELETE statements. But making modifications to this table will likely perturb the AUTOINCREMENT key generation algorithm.

这个SQL应该做你需要的东西：

UPDATE SQLITE_SEQUENCE SET seq = <n> WHERE name = <table>

其中n是你想设置和表是你的表名

来源

2015-10-18 00:43:12

我得到的序列此日志错误：E/SQLiteLog：（1）在“<”附近：语法错误 –

您是否将更改为所需的值？ –

是的，我做到了。下面是确切的代码行：db.execSQL（“UPDATE SQLITE_SEQUENCE SET seq = <1> WHERE name ='DRINK'”）; –

在Android中重置INTEGER PRIMARY KEY AUTOINCREMENT

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