Question

我只是将android和CRUD动作学习到SQLitedatabase中。它工作得很好。

我juste重命名数据库和表，然后我收到错误;

之前：

public static String DBName = "Example";
public static String tableName = "Resource";

后：

public static String DBName = "FAEXPED";
public static String tableName = "Client";

我的班级：

public class DBHelper extends SQLiteOpenHelper {

    public SQLiteDatabase DB;
    public String DBPath;
    public static String DBName = "FAEXPED";
    public static final int version = '1';
    public static Context currentContext;
    public static String tableName = "Client";

    public static final String KEY_CodeClient = "CodeClient";
    public static final String KEY_RsNom = "RaisonSocial";
    public static final String KEY_Ville = "Ville";
    public static final String KEY_Tel = "Tel"; 

    private static final String TAG = "Create_The_DB";

    private static final String TABLE_CREATE = "CREATE TABLE IF NOT EXISTS " +
            tableName + " ( "+ KEY_CodeClient + " VARCHAR PRIMARY KEY, "+ KEY_RsNom +"  VARCHAR," + KEY_Ville + "  VARCHAR,"+ KEY_Tel +"  VARCHAR)";

    public DBHelper(Context context) {
        //super(context, name, factory, version);
        // TODO Auto-generated constructor stub

        super(context, DBName, null, version);
        currentContext = context;
        DBPath = "/data/data/" + context.getPackageName() + "/databases";
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
      // TODO Auto-generated method stub
      Log.w(TAG, TABLE_CREATE);
      boolean dbExists = checkDbExists();       
      if (dbExists) {
        // do nothing

      } else {
        DB = currentContext.openOrCreateDatabase(DBName, 0, null);
        DB.execSQL(TABLE_CREATE);
    }

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // TODO Auto-generated method stub
         Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
                 + newVersion + ", which will destroy all old data");
               db.execSQL("DROP TABLE IF EXISTS " + TABLE_CREATE);
               onCreate(db);

    }

    private boolean checkDbExists() {
        SQLiteDatabase checkDB = null;

        try {
            String myPath = DBPath + DBName;
            checkDB = SQLiteDatabase.openDatabase(myPath, null,
                    SQLiteDatabase.OPEN_READONLY);

        } catch (SQLiteException e) {
            // database does't exist yet.
        }

        if (checkDB != null) {
            checkDB.close();
        }

        return checkDB != null ? true : false;
    }


}

我知道，当我重命名它时，它会为我创建一个新的DATABASE和一个新的TABLE，是该核心吗？

07-15 17:26:01.648: W/Create_The_DB(30510): CREATE TABLE IF NOT EXISTS Client ( CodeClient VARCHAR PRIMARY KEY, RaisonSocial  VARCHAR,Ville  VARCHAR,Tel  VARCHAR)
07-15 17:26:01.648: E/SQLiteLog(30510): (14) cannot open file at line 30247 of [00bb9c9ce4]
07-15 17:26:01.656: E/SQLiteLog(30510): (14) os_unix.c:30247: (2) open(/data/data/com.soft8.sql_test/databasesFAEXPED) - 
07-15 17:26:01.679: E/SQLiteDatabase(30510): Failed to open database '/data/data/com.soft8.sql_test/databasesFAEXPED'.
07-15 17:26:01.679: E/SQLiteDatabase(30510): android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
07-15 17:26:01.679: E/SQLiteDatabase(30510):    at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
07-15 17:26:01.679: E/SQLiteDatabase(30510):    at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:279)
07-15 17:26:01.679: E/SQLiteDatabase(30510):    at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:218)
07-15 17:26:01.679: E/SQLiteDatabase(30510):    at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:464)
07-15 17:26:01.679: E/SQLiteDatabase(30510):    at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:186)

Answer 1

这发生在我身上，在iOS上有些类似，尝试在每次CRUD操作后关闭与数据库的连接。一个提示，使用ORMLite是Android上Sqlite的一个很好的选择。

android数据库被锁定

1 个答案: