Question

我们一直致力于使用cocos2dx的Android应用程序。我们使用sqlite3在设备上本地存储数据。我们使用c ++代码连接和使用数据库。最近我们使用了交易，它在iOS平台上运行良好（cocos2dx应用程序是跨平台的）但它在android上失败了。

这很奇怪，因为只有事务中的更新查询失败，如果在循环中运行多个更新，那也是如此。每个其他查询（插入，删除，选择）在循环中运行良好。我们没有使用多个线程，所以无论运行什么，运行在主线程上我们都没有打开到数据库的多个连接。如果您关闭，相同的代码交易。我们不想放弃交易。一种解决方案是使用＆＃34;插入或替换＆＃34;查询而不是更新这是插入或插入删除但我不知道如果表具有外键关系会发生什么。我们可以如果我们假设数据是正确的，则删除外键约束。

对于每个查询，我们准备一个语句，逐步执行它然后最终确定它，以便即使查询也完成了每个语句失败。对于pragma设置以及开始和结束事务，我们使用的是包含上述过程的sqlite_exec。

这是一个测试日志： -

09-03 19:36:35.175: D/cocos2d-x debug info(30445): PRAGMA foreign_keys=ON 
09-03 19:36:35.175: D/cocos2d-x debug info(30445): begin transaction 
09-03 19:36:35.180: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): enter loop 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 2 where Test_ID = 133 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.185: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.190: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.190: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 2 where Test_ID = 135 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 2 where Test_ID = 135 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 1 where Test_ID = 140 
09-03 19:36:35.195: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 1 where Test_ID = 140 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 1 where Test_ID = 141 
09-03 19:36:35.200: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 1 where Test_ID = 141 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 1 where Test_ID = 142 
09-03 19:36:35.205: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 1 where Test_ID = 142 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 0 where Test_ID = 144 
09-03 19:36:35.215: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 0 where Test_ID = 144 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 0 where Test_ID = 146 
09-03 19:36:35.220: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 0 where Test_ID = 146 
09-03 19:36:35.225: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.225: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.225: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.225: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.225: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.225: D/cocos2d-x debug info(30445): update TestTable set ID_Type = 1 where Test_ID = 158 
09-03 19:36:35.230: D/cocos2d-x debug info(30445): Error 14 update TestTable set ID_Type = 1 where Test_ID = 158 
09-03 19:36:35.230: D/cocos2d-x debug info(30445): insert into TestTable(Test_ID) values(1) 
09-03 19:36:35.230: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.230: D/cocos2d-x debug info(30445): delete from TestTable where Test_ID = 1 
09-03 19:36:35.230: D/cocos2d-x debug info(30445): Executed 
09-03 19:36:35.230: D/cocos2d-x debug info(30445): select Test_ID, ID_Type from TestTable 
09-03 19:36:35.235: D/cocos2d-x debug info(30445): exit loop 
09-03 19:36:35.235: D/cocos2d-x debug info(30445): rollback

上面的日志表明它进入循环的位置以及退出循环的位置。在内部循环中，我们以相同的顺序执行更新，插入，删除和选择。您可以创建任何表并检查它。我不知道出了什么问题。我们检查了以下内容： -

没有多线程访问。
同时没有多个连接。
数据库和database_journal（事务的临时数据库）具有读写权限，否则即使插入和删除也会失败。
我们尝试开始立即交易
我们尝试关闭Synchronization pragma
我们在不同的Android设备（三星和micromax）上测试了

如果您放弃该事务，则相同的代码可以正常工作。

修改

你可以在android上试试这个，更新查询失败。如果您只是删除该交易，它将正常工作。您可以尝试插入，删除或选择所有这些工作正常。通常更新执行最大一次然后sqlite错误14＆＃34;无法打开数据库＆＃34;来了。

代码在这里：

sqlite3 *pSqliteConn = NULL;
    if (sqlite3_open(PATH_OF_DB.c_str(), &pSqliteConn) == SQLITE_OK)
    {
        bool success = true;

        char *pErrorMsg = NULL;
        int code = sqlite3_exec(pSqliteConn, "begin transaction", NULL, NULL, &pErrorMsg);
        if (pErrorMsg)
        {
            success = false;
            CCLog("Error %d %s", code, pErrorMsg);
            sqlite3_free(pErrorMsg);
        }
        else
        {
            CCLog("begin transaction");
        }

        for (int i = 0; i < 5; i++)
        {
            pErrorMsg = NULL;
            code = sqlite3_exec(pSqliteConn, "update Test_Table set ID_Type = 2 where Test_ID = 144", NULL, NULL, &pErrorMsg);
            if (pErrorMsg)
            {
                success = false;
                CCLog("Error %d %s", code, pErrorMsg);
                sqlite3_free(pErrorMsg);
            }
            else
            {
                CCLog("Executed");
            }
        }

        if (success)
        {
            pErrorMsg = NULL;
            code = sqlite3_exec(pSqliteConn, "commit", NULL, NULL, &pErrorMsg);

            if (pErrorMsg)
            {
                CCLog("Error %d %s", code, pErrorMsg);
                sqlite3_free(pErrorMsg);
            }
            else
            {
                CCLog("commit");
            }
        }
        else
        {
            pErrorMsg = NULL;
            code = sqlite3_exec(pSqliteConn, "rollback", NULL, NULL, &pErrorMsg);

            if (pErrorMsg)
            {
                CCLog("Error %d %s", code, pErrorMsg);
                sqlite3_free(pErrorMsg);
            }
            else
            {
                CCLog("rollback");
            }
        }

        sqlite3_close(pSqliteConn);
    }
    else
    {
        CCLog("connection failed");
    }

在Android中记录上述代码：

09-09 17:25:58.384: D/cocos2d-x debug info(12087): begin transaction
09-09 17:25:58.387: D/cocos2d-x debug info(12087): Executed
09-09 17:25:58.387: D/cocos2d-x debug info(12087): Error 14 unable to open database file
09-09 17:25:58.387: D/cocos2d-x debug info(12087): Error 14 unable to open database file
09-09 17:25:58.388: D/cocos2d-x debug info(12087): Error 14 unable to open database file
09-09 17:25:58.388: D/cocos2d-x debug info(12087): Error 14 unable to open database file
09-09 17:25:58.389: D/cocos2d-x debug info(12087): rollback

Answer 1

消息＆＃34;无法打开数据库文件＆＃34;在事务中第一个修改SQL语句表明SQLite无法创建回滚日志文件。

确保您具有对数据库目录的写访问权。

更新查询失败，启用事务sqlite3 + android + cocos2dx

1 个答案: