我正在开发一个使用 ormlite 和 sqlcipher 的应用程序。我需要在用户丢失所有数据的情况下重命名列。但是在更新该列之后 - 我无法使用 ormlite 的 queryForAll 方法。我试着寻找问题,但一点运气也没有。提前谢谢你。
这是我的更新表方法:
List<DB_RecordItem> recordItems;
List<JSONObject> objects = new ArrayList<>();
try {
// Add new column - file_id (instead of 'file')
db.execSQL(String.format("ALTER TABLE %s ADD COLUMN %s INTEGER;", DB_RecordItem.DB_TABLE, DB_File.DB_FILE));
// Get all items, which are going to be stored later.
recordItems = Database.getRecordItems().queryForAll();
Dao<DB_RecordItem, String> dao = DaoManager.createDao(connectionSource, DB_RecordItem.class);
Log.i("DatabaseLog", "Before delete table: " + dao.queryRaw("PRAGMA table_info(db_recorditem)").getResults().toString());
QueryBuilder<DB_RecordItem, String> qb = dao.queryBuilder();
// Query for all items.
for (DB_RecordItem item : recordItems) {
JSONObject jsonObject = new JSONObject(item.toJson());
Log.i("DatabaseLog", "Before: " + jsonObject.toString());
qb.where().eq("id", item.getId());
CloseableIterator<DB_RecordItem> iterator = dao.iterator(qb.prepare());
// Get old file id, since model id is changed to "file_id"
GenericRawResults<String[]> rawResults = dao.queryRaw("select file from db_recorditem where id = " + item.getId());
try {
int file_id = Integer.valueOf(rawResults.getResults().get(0)[0]);
if (file_id != -1) {
// If file_id it is not -1, then the recrod item had a file_id.
jsonObject.put(DB_File.DB_FILE, file_id);
}
} finally {
iterator.closeQuietly();
}
// Set all ids to 0, autoincrement will do its thing.
jsonObject.remove(DB_Core.DB_ID);
jsonObject.put(DB_Core.DB_ID, 0);
// Store new data.
objects.add(jsonObject);
}
// Drop old table, with column that we don't need any more.
TableUtils.dropTable(connectionSource, DB_RecordItem.class, false);
// Create new table with correct column naming.
TableUtils.createTable(connectionSource, DB_RecordItem.class);
Log.i("DatabaseLog", "New table: " + dao.queryRaw("PRAGMA table_info(db_recorditem)").getResults().toString());
// Store all data.
for (JSONObject object : objects) {
Log.i("DatabaseLog", "After: " + object.toString());
new DB_RecordItem(object).save();
}
Log.i("DatabaseLog", "Done!");
} catch (Exception e) {
Log.i("DatabaseLog", "Crash.");
e.printStackTrace();
}
上面的代码似乎可以完美运行,没有任何错误。但是,在我尝试继续执行此行后出现错误:
// getRecordItems() returns Dao<DB_RecordItem, Integer>
Database.getRecordItems().queryForAll()
看来问题出在新插入的字段上。如果字段没有“file_id”的值,一切正常。但如果确实如此 - 错误会重现。我是否有可能需要重新生成 ormlite config_file ?
我的错误信息是:
E/CursorWindow﹕ Bad request for field slot 0,17. numRows = 1, numColumns = 17
W/System.err﹕ java.lang.IllegalStateException: get field slot from row 0 col 17 failed
W/System.err﹕ at net.sqlcipher.CursorWindow.getLong_native(Native Method)
W/System.err﹕ at net.sqlcipher.CursorWindow.getInt(CursorWindow.java:522)
W/System.err﹕ at net.sqlcipher.AbstractWindowedCursor.getInt(AbstractWindowedCursor.java:95)
W/System.err﹕ at android.database.CursorWrapper.getInt(CursorWrapper.java:102)
W/System.err﹕ at com.j256.ormlite.sqlcipher.android.AndroidDatabaseResults.getInt(AndroidDatabaseResults.java:168)
W/System.err﹕ at com.j256.ormlite.field.types.IntegerObjectType.resultToSqlArg(IntegerObjectType.java:37)
W/System.err﹕ at com.j256.ormlite.field.BaseFieldConverter.resultToJava(BaseFieldConverter.java:24)
W/System.err﹕ at com.j256.ormlite.field.FieldType.resultToJava(FieldType.java:819)
W/System.err﹕ at com.j256.ormlite.stmt.mapped.BaseMappedQuery.mapRow(BaseMappedQuery.java:60)
W/System.err﹕ at com.j256.ormlite.stmt.SelectIterator.getCurrent(SelectIterator.java:270)
W/System.err﹕ at com.j256.ormlite.stmt.SelectIterator.nextThrow(SelectIterator.java:161)
W/System.err﹕ at com.j256.ormlite.stmt.StatementExecutor.query(StatementExecutor.java:202)
W/System.err﹕ at com.j256.ormlite.stmt.StatementExecutor.queryForAll(StatementExecutor.java:118)
W/System.err﹕ at com.j256.ormlite.dao.BaseDaoImpl.queryForAll(BaseDaoImpl.java:241)
W/System.err﹕ at database.Database$ObjectsIterator.start(Database.java:221)
W/System.err﹕ at fragments.F_BackupLocal$LocalBackup.doInBackground(F_BackupLocal.java:429)
W/System.err﹕ at fragments.F_BackupLocal$LocalBackup.doInBackground(F_BackupLocal.java:368)
W/System.err﹕ at android.os.AsyncTask$2.call(AsyncTask.java:288)
W/System.err﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:237)
W/System.err﹕ at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
只要找到问题所在,我就会更新这篇文章。
最佳答案
我终于解决了这个问题。
According to this documentation - In SQLite, all you can do is rename a table name and add a new column. You can’t rename or remove a column or change the constraints.
我最终的解决方案是用新字段追加表格,并保留旧字段。
private void renameDB_Record_Item_Columns(ConnectionSource connectionSource) {
List<DB_RecordItem> recordItems;
List<JSONObject> objects = new ArrayList<>();
try {
Dao<DB_RecordItem, String> dao = DaoManager.createDao(connectionSource, DB_RecordItem.class);
dao.executeRaw(String.format("ALTER TABLE %s ADD COLUMN %s INTEGER;", "db_recorditem", "file_id"));
recordItems = Database.getRecordItems().queryForAll();
QueryBuilder<DB_RecordItem, String> qb = dao.queryBuilder();
// Query for all items.
for (DB_RecordItem item : recordItems) {
qb.where().eq("id", item.getId());
CloseableIterator<DB_RecordItem> iterator = dao.iterator(qb.prepare());
GenericRawResults<String[]> rawResults = dao.queryRaw("select file from db_recorditem where id = " + item.getId() + ";");
try {
int file_id = Integer.valueOf(rawResults.getResults().get(0)[0]);
if (file_id != -1) {
// If file_id it is not -1, then the recrod item had a file_id.
item.assignFile(new DB_File().setId(file_id));
item.update();
}
} finally {
iterator.closeQuietly();
}
}
} catch (Exception e) {
Log.i("DatabaseLog", "Crash.");
e.printStackTrace();
}
}
无论如何,如果有人找到删除和重新创建表的正确方法,请分享。 :)
关于android - 更新表后的 Ormlite 我不能对所有方法使用查询,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/29580037/