SQLiteDatabaseLockedException：数据库被锁定，超过重试次数

Question

我正在做库存管理应用程序，它需要经常访问数据库来查看和编辑数据。多次重复此过程，数据库被锁定。

得到 2 错误： “数据库的 SQLiteConnection 对象已泄露！请修复您的应用程序以正确结束正在进行的事务并在不再需要时关闭数据库。”

“SQLiteDatabaseLockedException：数据库被锁定（代码 5）：超出重试次数”

收到此错误后，需要很长时间才能完成数据库插入操作。

我该如何解决这个问题。

public synchronized boolean insert(BeanOrderHeader orderHdrItem) throws Exception {
    boolean status=false;

    try {

        //Create Sqlite object to insert order details
        db = getSQLiteDatabase();

        //Before insert delete records if already exists
        deleteOrderData(db,orderHdrItem);

        db.beginTransactionNonExclusive();
        // db.beginTransaction();



        getPaymentPreparedStatement(db,orderHdrItem);


        status= true; 
        db.setTransactionSuccessful();

        db.endTransaction();


        if(orderHdrItem.isNewOrder())
            mCounterProvider.updateOrderBillNumber();

    } catch (Exception e) {

        e.printStackTrace();

        status= false;
        throw new Exception("Failed to save the order. Please check the log for details");
    }finally{
    db.setTransactionSuccessful();
    db.endTransaction();
    }
    return status;
}

 protected SQLiteDatabase getSQLiteDatabase() {
    if(myDataBase==null)
        open();

    if(!myDataBase.isOpen())
        open();
    return myDataBase;

}


  public SQLiteStatement getPaymentPreparedStatement(SQLiteDatabase db,BeanOrderHeader         
     orderHeader) throws Exception{
    ArrayList<BeanOrderPayment> orderPaymentlList=orderHeader.getOrderPaymentItems();
    SQLiteStatement prep;
    String insert_sql="insert into "+"order_payments "+" (" +               
            "order_id, "+                   
            "payment_mode, "+                   
            "paid_amount, "+                    
            "card_name, "+                  
            "card_type, "+                  
            "card_no, "+                    
            "name_on_card, "+               
            "card_expiry_month, "+                  
            "card_expiry_year, "+                   
            "card_approval_code, "+ 
            "card_account_type, "+
            "company_id, "+                 
            "voucher_id, "+                 
            "voucher_value, "+                  
            "voucher_count, "+                  
            "cashier_id, "+ 
            "payment_date, " +
            "payment_time "+                    
            ",id " +
            ",discount_id" +
            ",discount_code" +
            ",discount_name" +
            ",discount_description" +
            ",discount_price" +
            ",discount_is_percentage" +
            ",discount_is_overridable" +
            ",discount_amount" +
            ",is_repayment" +
            ",is_voucher_balance_returned" +
            ",partial_balance" +
            ") "+
            " values (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)";
    prep=db.compileStatement(insert_sql);
    int counter=0;
    if(mPosOrderUtil==null)
    mPosOrderUtil=new PosOrderUtil(getContext());
    for (BeanOrderPayment payItem: orderPaymentlList){  
        prep.bindString(1, payItem.getOrderId());
        prep.bindLong(2, payItem.getPaymentMode().getValue());
        prep.bindDouble(3, payItem.getPaidAmount());
        prep.bindString(4, payItem.getCardName());
        prep.bindString(5, payItem.getCardType());
        prep.bindString(6, payItem.getCardNo());
        prep.bindString(7, payItem.getNameOnCard());
        prep.bindLong(8, payItem.getCardExpiryMonth());
        prep.bindLong(9, payItem.getCardExpiryYear());
        prep.bindString(10, payItem.getCardApprovalCode());
        prep.bindString(11, payItem.getAccount());
        prep.bindLong(12, payItem.getCompanyId());
        prep.bindLong(13, payItem.getVoucherId());
        prep.bindDouble(14, payItem.getVoucherValue());
        prep.bindLong(15, payItem.getVoucherCount());
        prep.bindLong(16, payItem.getCashierID());
        prep.bindString(17, payItem.getPaymentDate());
        prep.bindString(18, payItem.getPaymentTime());
        prep.bindString(19, mPosOrderUtil.appendToId(orderHeader.getOrderId(), counter++)); //Id generated from order id
        BeanDiscount disc=payItem.getDiscount();
        if(disc!=null){
            prep.bindLong(20, disc.getId());
            prep.bindString(21, disc.getCode());
            prep.bindString(22, disc.getName());
            prep.bindString(23, disc.getDescription());
            prep.bindDouble(24, disc.getPrice());
            prep.bindLong(25, getIntFromBoolean(disc.isPercentage()));
            prep.bindLong(26, getIntFromBoolean(disc.isOverridable()));
            prep.bindDouble(27, payItem.getPaidAmount());
        }
        prep.bindLong(28, getIntFromBoolean(payItem.isRepayment()));
        prep.bindLong(29, getIntFromBoolean(payItem.isVoucherBalanceReturned()));
        prep.bindDouble(30, payItem.getPartialBalance());
        prep.executeInsert();
        prep.clearBindings();
    }   
    return prep;
} 

Answer 1

您需要在数据库操作后关闭您的 SQLiteHelper 类实例

dbHelper.close()

Answer 2

最后我通过保留 SQLiteDatabase 实例的单个对象来解决问题。如果数据库结构复杂，使用单个对象访问所有表中的数据，这样我们就可以轻松管理 sq-lite 数据库。

数据库操作后关闭数据库对象以解决数据库泄漏

 mDatabase.close()

Answer 3

这个 SQLiteDatabaseLockedException 的另一个原因是开始一个事务，而不是在 finally 块中关闭它，然后尝试对数据库做一些事情。

不好：

 SQLiteDatabase db = this.getReadableDatabase();
 db.beginTransaction();
 //DO some db writing
 db.setTransactionSuccessful();
 db.endTransaction();

好：

 SQLiteDatabase db = this.getReadableDatabase();
 db.beginTransaction();
 try {
   //DO some db writing
   db.setTransactionSuccessful();
 } finally {
    db.endTransaction();
 }