更新
我找到了这个链接
http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/
任何人都可以解释如何使用此
编写更新/插入语句___________________________________________________________________________
问题
我正在尝试创建一种方法，我可以将存储在sqllite数据库中的数据复制到我的应用程序的数据库中。结构类似。我只是不想逐个插入行。
我正在寻找一种方法，通过该方法将存储在assets文件夹或外部存储器中的预先输入的数据复制到我的应用程序db。
我无法在我的应用中填充数据。我不想为每一行和每列编写5000个插入语句。
任何人都可以建议一种方法。我是android的新手，所以请详细解释或提供链接。
我的数据库帮助程序类
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DBHelper extends SQLiteOpenHelper {
public SQLiteDatabase db1;
// Static Final Variable database meta information
static final String DATABASE = "assesmenttool.db";
static final int DATABASE_VERSION = 1;
//Table Student Details
static final String TABLEStudent = "StudentDetails";
static final String S_ID = "_id";
static final String SchoolID = "SchoolID";
static final String SchoolName = "schoolname";
static final String StudentFirstName = "StudentFirstName";
static final String StudentLastName ="StudentLastName";
static final String StudentClassLevel ="StudentClassLevel";
static final String RollNo="RollNo";
static final String TestDate ="TestDate";
//Table Response Details
static final String TABLEResponse = "TableResponse";
static final String R_ID = "_id";
static final String StudentID = "StudentID";
static final String R_QuestionID = "QuestionID";
static final String QuestOptionID = "QuestOptionID";
//Table Question Master
static final String TableQuestionMaster = "TableQuestionMaster";
static final String Q_ID= "_id";
static final String Module_ID = "Module_ID";
static final String SubModule_ID = "SubModule_ID";
static final String SubModuleQuestion_ID ="SubModuleQuestion_ID";
static final String Question_ID= "Question_ID";
static final String Title = "Title";
static final String Module = "Module";
static final String TitleDescription = "TitleDescription";
static final String QuestionText = "QuestionText";
static final String QuestionImage = "QuestionImage";
static final String QuestionTemplate = "QuestionTemplate";
static final String CorrectOptionID = "CorrectOptionID";
//Table Template Master
static final String TableTemplateMaster = "TemplateMaster";
static final String T_ID= "_id";
static final String Template_ID= "Template_ID";
static final String Name = "Name";
static final String Description = "Description";
//Table Question Option
static final String TableQuestionOption = "TableQuestionOption";
static final String TQP_ID= "_id";
static final String TQP_QuestionID = "QuestionID";
static final String OptionText = "OptionText";
//Table Class Master
static final String TableClassMaster = "TableClassMaster";
static final String Class_ID= "_id";
static final String Class = "class";
// Override constructor
public DBHelper(Context context) {
super(context, DATABASE, null, DATABASE_VERSION);
}
// Override onCreate method
@Override
public void onCreate(SQLiteDatabase db) {
//Create Table Student Details
db.execSQL("CREATE TABLE " + TABLEStudent + " ( " + S_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + SchoolID + " text, "
+ SchoolName + " text, " + StudentFirstName + " text, " + StudentLastName + " text, " + RollNo + " text," + TestDate + " text," + StudentClassLevel + " text)");
//Create Table Response Details
db.execSQL("CREATE TABLE " + TABLEResponse + " ( " + R_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + StudentID + " text, "
+ R_QuestionID + " text, " + QuestOptionID + " text)");
//Create Table Question Master
db.execSQL("CREATE TABLE " + TableQuestionMaster + " ( " + Q_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + Question_ID + " text, " + Module_ID + " text, " + SubModule_ID + " text, " + SubModuleQuestion_ID + " text, " + Title + " text, " + Module + " text,"
+ TitleDescription + " text, " + QuestionText + " text, " + QuestionImage + " text, " + QuestionTemplate + " text," + CorrectOptionID + " text)");
//Create Table Template Master
db.execSQL("CREATE TABLE " + TableTemplateMaster + " ( " + T_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + Name + " text, "
+ Description + " text)");
//Create Table Question Option
db.execSQL("CREATE TABLE " + TableQuestionOption + " ( " + TQP_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + TQP_QuestionID + " text, "
+ OptionText + " text)");
//Create Table Class Master
db.execSQL("CREATE TABLE " + TableClassMaster + " ( " + Class_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + Class + " text)");
}
public List<String> getAllClasses(){
List<String> labels = new ArrayList<String>();
// Select All Query
String selectQuery = "SELECT * FROM " + TableClassMaster;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
labels.add(cursor.getString(1));
} while (cursor.moveToNext());
}
// closing connection
cursor.close();
db.close();
// returning lables
return labels;
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop old version table
db.execSQL("Drop table " + TABLEStudent);
db.execSQL("Drop table " + TABLEResponse);
db.execSQL("Drop table " + TableQuestionMaster);
db.execSQL("Drop table " + TableTemplateMaster);
db.execSQL("Drop table " + TableQuestionOption);
db.execSQL("Drop table " + TableClassMaster);
// Create New Version table
onCreate(db);
}
}
我在stackoverflow上找到的SQLLITE副本
我如何将这两者混合在一起。我如何同步这两个sqllite表。 ？
private static final String DB_NAME = "asset.db";
private Context context;
public AssetDatabaseOpenHelper(Context context) {
this.context = context;
}
public SQLiteDatabase openDatabase() {
File dbFile = context.getDatabasePath(DB_NAME);
if (!dbFile.exists()) {
try {
copyDatabase(dbFile);
} catch (IOException e) {
throw new RuntimeException("Error creating source database", e);
}
}
return SQLiteDatabase.openDatabase(dbFile.getPath(), null, SQLiteDatabase.OPEN_READONLY);
}
private void copyDatabase(File dbFile) throws IOException {
InputStream is = context.getAssets().open(DB_NAME);
OutputStream os = new FileOutputStream(dbFile);
byte[] buffer = new byte[1024];
while (is.read(buffer) > 0) {
os.write(buffer);
}
os.flush();
os.close();
is.close();
}
}
答案 0 :(得分：1)
这将解决我的答案..
只需使用sqlliteOPenHelper Class ..
的帮助<强>步骤1
添加copyDataBase（）函数..
<强>第二步
像你这样在你的MainActivity中启动它
helper = new DBHelper(this);
try {
helper.createDataBase();
} catch (IOException ioe) {
throw new Error("Unable to create database");
}
try {
helper.openDataBase();
}catch(SQLException sqle){
throw sqle;
}
您的DBHelper课程类似
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBHelper extends SQLiteOpenHelper {
public SQLiteDatabase db1;
// Static Final Variable database meta information
static final String DATABASE = "assesmenttool.db";
static final int DATABASE_VERSION = 1;
//Table Student Details
static final String TABLEStudent = "StudentDetails";
static final String S_ID = "_id";
static final String SchoolID = "SchoolID";
static final String SchoolName = "schoolname";
static final String StudentFirstName = "StudentFirstName";
static final String StudentLastName ="StudentLastName";
static final String StudentClassLevel ="StudentClassLevel";
static final String RollNo="RollNo";
static final String TestDate ="TestDate";
//Table Response Details
static final String TABLEResponse = "TableResponse";
static final String R_ID = "_id";
static final String StudentID = "StudentID";
static final String R_QuestionID = "QuestionID";
static final String QuestOptionID = "QuestOptionID";
//Table Question Master
static final String TableQuestionMaster = "TableQuestionMaster";
static final String Q_ID= "_id";
static final String Module_ID = "Module_ID";
static final String SubModule_ID = "SubModule_ID";
static final String SubModuleQuestion_ID ="SubModuleQuestion_ID";
static final String Question_ID= "Question_ID";
static final String Title = "Title";
static final String Module = "Module";
static final String TitleDescription = "TitleDescription";
static final String QuestionText = "QuestionText";
static final String QuestionImage = "QuestionImage";
static final String QuestionTemplate = "QuestionTemplate";
static final String CorrectOptionID = "CorrectOptionID";
//Table Template Master
static final String TableTemplateMaster = "TemplateMaster";
static final String T_ID= "_id";
static final String Template_ID= "Template_ID";
static final String Name = "Name";
static final String Description = "Description";
//Table Question Option
static final String TableQuestionOption = "TableQuestionOption";
static final String TQP_ID= "_id";
static final String TQP_QuestionID = "QuestionID";
static final String TQP_OptionID = "TQP_OptionID";
static final String OptionText = "OptionText";
//Table Class Master
static final String TableClassMaster = "TableClassMaster";
static final String Class_ID= "_id";
static final String Class = "class";
private static String DB_PATH = "/data/data/com.cldonline.assesmenttool/databases/";
private static String DB_NAME = "assesmenttool.db";
private SQLiteDatabase myDataBase;
private final Context myContext;
/**
* Constructor
* Takes and keeps a reference of the passed context in order to access to the application assets and resources.
* @param context
*/
public DBHelper(Context context) {
super(context, DB_NAME, null, 1);
this.myContext = context;
}
/**
* Creates a empty database on the system and rewrites it with your own database.
* */
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
if(dbExist){
//do nothing - database already exist
}else{
//By calling this method and empty database will be created into the default system path
//of your application so we are gonna be able to overwrite that database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
/**
* Check if the database already exist to avoid re-copying the file each time you open the application.
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase(){
SQLiteDatabase checkDB = null;
try{
String myPath = DB_PATH + DB_NAME;
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;
}
/**
* Copies your database from your local assets-folder to the just created empty database in the
* system folder, from where it can be accessed and handled.
* This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException{
//Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DB_NAME);
// Path to the just created empty db
String outFileName = DB_PATH + DB_NAME;
//Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
//transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer))>0){
myOutput.write(buffer, 0, length);
}
//Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
}
// Override onCreate method
@Override
public void onCreate(SQLiteDatabase db) {
}
public List<String> getAllClasses(){
List<String> labels = new ArrayList<String>();
// Select All Query
String selectQuery = "SELECT * FROM " + TableClassMaster;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
labels.add(cursor.getString(1));
} while (cursor.moveToNext());
}
// closing connection
cursor.close();
db.close();
// returning lables
return labels;
}
public List<String> getAllOptions(String Qid){
List<String> options = new ArrayList<String>();
// Select All Query
String selectQuery = "SELECT * FROM " + TableQuestionOption +" "+"where QuestionID ='"+Qid+"'";
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
options.add(cursor.getString(2));
} while (cursor.moveToNext());
}
// closing connection
cursor.close();
db.close();
// returning lables
return options;
}
public void openDataBase() throws SQLException{
//Open the database
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}
@Override
public synchronized void close() {
if(myDataBase != null)
myDataBase.close();
super.close();
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
public ArrayList<Cursor> getData(String Query){
//get writable database
SQLiteDatabase sqlDB = this.getWritableDatabase();
String[] columns = new String[] { "mesage" };
//an array list of cursor to save two cursors one has results from the query
//other cursor stores error message if any errors are triggered
ArrayList<Cursor> alc = new ArrayList<Cursor>(2);
MatrixCursor Cursor2= new MatrixCursor(columns);
alc.add(null);
alc.add(null);
try{
String maxQuery = Query ;
//execute the query results will be save in Cursor c
Cursor c = sqlDB.rawQuery(maxQuery, null);
//add value to cursor2
Cursor2.addRow(new Object[] { "Success" });
alc.set(1,Cursor2);
if (null != c && c.getCount() > 0) {
alc.set(0,c);
c.moveToFirst();
return alc ;
}
return alc;
} catch(SQLException sqlEx){
Log.d("printing exception", sqlEx.getMessage());
//if any exceptions are triggered save the error message to cursor an return the arraylist
Cursor2.addRow(new Object[] { ""+sqlEx.getMessage() });
alc.set(1,Cursor2);
return alc;
} catch(Exception ex){
Log.d("printing exception", ex.getMessage());
//if any exceptions are triggered save the error message to cursor an return the arraylist
Cursor2.addRow(new Object[] { ""+ex.getMessage() });
alc.set(1,Cursor2);
return alc;
}
}
}
答案 1 :(得分：0)
我用同样的方法。我有一个帮助类：
public class DatabaseImport {
private static final String TAG = "DataAdapter";
private final DataBaseHelper mDbHelper;
public DatabaseImport(Context context) {
Context mContext = context;
mDbHelper = new DataBaseHelper(mContext);
}
public void createDatabase() {
try {
mDbHelper.createDataBase();
} catch (Exception mIOException) {
Log.e(TAG, mIOException.toString() + " UnableToCreateDatabase");
throw new Error("UnableToCreateDatabase");
}
}
。
class DataBaseHelper extends SQLiteOpenHelper {
//The Android's default system path of your application database.
private static String DB_PATH = "/data/data/yourpackagename/databases/";
private static final String DB_NAME = "databasename";
private static final String TAG = "DataBaseHelper"; // Tag just for the LogCat window
//destination path (location) of our database on device
private final Context mContext;
private SQLiteDatabase mDataBase;
public DataBaseHelper(Context context) {
super(context, DB_NAME, null, 1);// 1? its Database Version
if (android.os.Build.VERSION.SDK_INT >= 17) {
DB_PATH = context.getApplicationInfo().dataDir + "/databases/";
} else {
DB_PATH = "/data/data/" + context.getPackageName() + "/databases/";
}
this.mContext = context;
}
public void createDataBase() {
//If database not exists copy it from the assets
boolean mDataBaseExist = checkDataBase();
if (!mDataBaseExist) {
this.getReadableDatabase();
this.close();
try {
//Copy the database from assests
copyDataBase();
Log.e(TAG, "createDatabase database created");
} catch (IOException mIOException) {
throw new Error("ErrorCopyingDataBase");
}
}
}
//Check that the database exists here: /data/data/your package/databases/Da Name
private boolean checkDataBase() {
File dbFile = new File(DB_PATH + DB_NAME);
//Log.v("dbFile", dbFile + " "+ dbFile.exists());
return dbFile.exists();
}
//Copy the database from assets
private void copyDataBase() throws IOException {
InputStream mInput = mContext.getResources().openRawResource(R.raw.kindersporttabelle);
String outFileName = DB_PATH + DB_NAME;
OutputStream mOutput = new FileOutputStream(outFileName);
byte[] mBuffer = new byte[1024];
int mLength;
while ((mLength = mInput.read(mBuffer)) > 0) {
mOutput.write(mBuffer, 0, mLength);
}
mOutput.flush();
mOutput.close();
mInput.close();
}
@Override
public synchronized void close() {
if (mDataBase != null)
mDataBase.close();
super.close();
}
@Override
public void onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
使用普通的DataBaseHandler可以访问和使用数据库：
public class DatabaseHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
//databasename
private static final String DATABASE_NAME = "databasename";
//table names
[...]
//game name column names
[....]
private static Context myContext;
private static DatabaseHandler mInstance = null;
/**
* Constructor
* Takes and keeps a reference of the passed context in order to access to the application assets and resources.
*/
private DatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public static DatabaseHandler getInstance(Context context) {
if (mInstance == null) {
mInstance = new DatabaseHandler(context.getApplicationContext());
}
myContext = context;
return mInstance;
}
@Override
public void onCreate(SQLiteDatabase db) {
Intent intent = new Intent(myContext, MainActivity.class);
myContext.startActivity(intent);
DatabaseImport mDbHelper = new DatabaseImport(myContext);
try {
mDbHelper.createDatabase();
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + tablename);
myContext.deleteDatabase(DATABASE_NAME);
onCreate(db);
}
}
你只需要调整正确的班级名称。这应该工作。祝好运。
答案 2 :(得分：0)
检查this。提供位于项目资产文件夹中的数据库路径。您可以在SQLiteOpenHelper的帮助下复制整个数据库。
public class PlanDetailsSQLiteOpenHelper extends SQLiteOpenHelper {
private static final String TAG = "SQLiteOpenHelper";
private final Context context;
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "my_custom_db";
private boolean createDb = false, upgradeDb = false;
public PlanDetailsSQLiteOpenHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.context = context;
}
/**
* Copy packaged database from assets folder to the database created in the
* application package context.
*
* @param db
* The target database in the application package context.
*/
private void copyDatabaseFromAssets(SQLiteDatabase db) {
Log.i(TAG, "copyDatabase");
InputStream myInput = null;
OutputStream myOutput = null;
try {
// Open db packaged as asset as the input stream
myInput =context.getAssets().open("your_database_path");
// Open the db in the application package context:
myOutput = new FileOutputStream(db.getPath());
// Transfer db file contents:
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
myOutput.flush();
// Set the version of the copied database to the current
// version:
SQLiteDatabase copiedDb = context.openOrCreateDatabase(
DATABASE_NAME, 0, null);
copiedDb.execSQL("PRAGMA user_version = " + DATABASE_VERSION);
// copiedDb.close();
} catch (IOException e) {
e.printStackTrace();
throw new Error(TAG + " Error copying database");
} finally {
// Close the streams
try {
if (myOutput != null) {
myOutput.close();
}
if (myInput != null) {
myInput.close();
}
} catch (IOException e) {
e.printStackTrace();
throw new Error(TAG + " Error closing streams");
}
}
}
@Override
public void onCreate(SQLiteDatabase db) {
Log.i(TAG, "onCreate db");
createDb = true;
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.i(TAG, "onUpgrade db");
upgradeDb = true;
}
@Override
public void onOpen(SQLiteDatabase db) {
Log.i(TAG, "onOpen db");
if (createDb) {// The db in the application package
// context is being created.
// So copy the contents from the db
// file packaged in the assets
// folder:
createDb = false;
copyDatabaseFromAssets(db);
}
if (upgradeDb) {// The db in the application package
// context is being upgraded from a lower to a higher version.
upgradeDb = false;
// Your db upgrade logic here:
}
}
}