使用SQLiteOpenHelper在Android中连接sqlite数据库

我正在创建一个数据库,该数据库引用另一个数据库中的键.本质上,我要导入的数据要与将要更改的数据分开,但是如果可能的话,我想通过外键引用其他键.据我所知,我需要先附加数据库才能实现这一点.到目前为止,这是相关的代码：

public class LogDatabaseHelper extends SQLiteOpenHelper {

    private static final String DATABASE_NAME = "log.db";
    private static final int DATABASE_VERSION = 1;
    private String namesDb;

    public LogDatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        namesDb=getNamesDbPath();

    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("ATTACH DATABASE ? AS names",new String[]{namesDb});
        StringBuilder query=new StringBuilder();
        query.append("CREATE TABLE log (");
    }
}

但是,这似乎不起作用,因为出现了以下错误：

11-21 17:35:58.176: E/SQLiteLog(9984): (1) statement aborts at 5: [ATTACH DATABASE ? AS names] cannot ATTACH database within transaction
11-21 17:35:58.176: D/AndroidRuntime(9984): Shutting down VM
11-21 17:35:58.176: W/dalvikvm(9984): threadid=1: thread exiting with uncaught exception (group=0x41a21700)
11-21 17:35:58.191: E/AndroidRuntime(9984): FATAL EXCEPTION: main
11-21 17:35:58.191: E/AndroidRuntime(9984): android.database.sqlite.SQLiteException: cannot ATTACH database within transaction (code 1)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteConnection.nativeExecuteForChangedRowCount(Native Method)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteConnection.executeForChangedRowCount(SQLiteConnection.java:734)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteSession.executeForChangedRowCount(SQLiteSession.java:754)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteStatement.executeUpdateDelete(SQLiteStatement.java:64)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1674)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1603)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at com.kd7uiy.hamfinder.LogDatabaseHelper.onCreate(LogDatabaseHelper.java:27)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:252)
11-21 17:35:58.191: E/AndroidRuntime(9984):     at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:164)

我该如何进行这项工作？

解决方法:

我想出了一种使它起作用的方法,虽然我对此并不感到特别骄傲,但是它确实起作用.如果附加数据库时无法进行事务处理,请先结束事务处理.

db.setTransactionSuccessful();
db.endTransaction();
db.execSQL("ATTACH DATABASE ? AS names",new String[]{namesDb});
db.beginTransaction();

标签：sqlite,android-sqlite,android
来源： https://codeday.me/bug/20191030/1965826.html