SQLiteStudio 是一个跨平台的 SQLite 数据库的规画工具,接管 Tcl 语言开拓。
SQLiteStudio的特色:
功能美满的sqlite2以及sqlite3工具,视图编码反对于utf8。
反对于导出数据格式:csv、html、plain、sql、xml,
可同时掀开多个数据库文件
反对于魔难以及编纂二进制字段
SqliteStudio奈何样用?
运用“sqlitestudio”掀开(也可能运用此外sqlite可视化工具,总体习气运用该工具,多语言小巧无需装置)
一、掀开sqlitestudio ”数据库“-”削减数据库“
二、抉择导出的那个数据库文件直接掀开即可。
三、在sqlitestudio 可能建树以及更正表也可能实施SQL语句根基可能知足罕用需要
在sqlitestudio 导出表数据直接右键”导出表“ 默认格式CSV文件
四、导入表数据:
右键表名“import data to table”
SqliteStudio在Android挨次中运用已经有的SQLite数据库
1. 豫备SQLite database文件
假如你已经建树了一个sqlite数据库,咱们需要对于其妨碍一些更正。
(译者注:这里原文是推选了一个SQLite数据库规画软件,这个我感应可能随自己的喜爱,最Windows下面有多款可视化的SQlite数据库规画软件,可能利便的读取,编纂数据库,好比我用的是sqlitestudio
掀开数据库,削减一个新的table “android_metadata",插入一行数据,详细的SQL如下:
[sql] view plaincopyprint?在CODE上魔难代码片派生到我的代码片
CREATE TABLE "android_metadata" ("locale" TEXT DEFAULT 'en_US')
INSERT INTO "android_metadata" VALUES ('en_US')
(译者注:下面两行是表明需要妨碍的操作,详细可能直接在sqlitesstudio中实现)
而后你需要对于你数据表格的primary id 列重命名为 “_id”,这样Adroid会知道奈何样对于id列妨碍绑定,你可能很简略的在SQlite数据库规画软件中妨碍列编纂。
这两步之后,你的sqlite数据库文件就豫备好了。
(译者注:这里我保存了id列,即不对于其妨碍重命名,测试证实也是不下场的)
2. 在你的Android挨次中复制,掀开以及碰头数据库
如今把你上一步豫备好的数据库文件放在“assets”文件夹下面,而后经由秉持 SQLiteOpenHelper类来建树一个Database Helper类,
你的DataBaseHelper类简陋可能如下:
public class DataBaseHelper extends SQLiteOpenHelper{
//The Android's default system path of your application database.
private static String DB_PATH = "/data/data/YOUR_PACKAGE/databases/";
private static String DB_NAME = "myDBName";
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 DataBaseHelper(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();
}
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 onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
// Add your public helper methods to access and get content from the database.
// You could return cursors by doing "return myDataBase.query(....)" so it'd be easy
// to you to create adapters for your views.
}
就这样。
如今你可能建树一个新的DataBaseHelper实例,而后调用createDataBase(),而后再调用openDataBase()措施,记住更正DB_PATH字符串中“YOUR_PACKAGE”为你真正的package称谓(也便是说com.examplename.myapp)
如下是树模代码:
[java] view plaincopyprint?在CODE上魔难代码片派生到我的代码片
...
DataBaseHelper myDbHelper = new DataBaseHelper();
myDbHelper = new DataBaseHelper(this);
try {
myDbHelper.createDataBase();
} catch (IOException ioe) {
throw new Error("Unable to create database");
}
try {
myDbHelper.openDataBase();
}catch(SQLException sqle){
throw sqle;
}
...