Android SQLite資料庫demo
阿新 • • 發佈：2018-11-09
demo連結：https://download.csdn.net/download/meixi_android/10710400
建立資料庫版本v.1
/** * 作者：created by meixi * 郵箱：[email protected] * 日期：2018/10/9 11 */ public class DBHelper extends SQLiteOpenHelper { private static final String DATABASE_NAME = "mall.db"; private static final int DATABASE_VERSION = 1000; private static DBHelper instance = null; public DBHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } public synchronized static DBHelper getInstance(Context context) { if (instance == null) { instance = new DBHelper(context); } return instance; } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(SQL.CREATE_TABLE_FAVORITE); // 若不是第一個版本安裝，直接執行資料庫升級 // 請不要修改FIRST_DATABASE_VERSION的值，其為第一個資料庫版本大小 final int FIRST_DATABASE_VERSION = 1000; onUpgrade(db, FIRST_DATABASE_VERSION, DATABASE_VERSION); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // 使用for實現跨版本升級資料庫 for (int i = oldVersion; i < newVersion; i++) { switch (i) { default: break; } } } }
建立資料庫版本v.2
public class DBHelper2 extends SQLiteOpenHelper { private static final String DATABASE_NAME = "mall.db"; private static final int DATABASE_VERSION = 1001; private static DBHelper2 instance = null; public DBHelper2(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } public synchronized static DBHelper2 getInstance(Context context) { if (instance == null) { instance = new DBHelper2(context); } return instance; } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(SQL.CREATE_TABLE_FAVORITE); // 若不是第一個版本安裝，直接執行資料庫升級 // 請不要修改FIRST_DATABASE_VERSION的值，其為第一個資料庫版本大小 final int FIRST_DATABASE_VERSION = 1000; onUpgrade(db, FIRST_DATABASE_VERSION, DATABASE_VERSION); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // 使用for實現跨版本升級資料庫 for (int i = oldVersion; i < newVersion; i++) { switch (i) { case 1000: upgradeToVersion1001(db); break; default: break; } } } private void upgradeToVersion1001(SQLiteDatabase db){ // favorite表新增1個欄位 String sql1 = "ALTER TABLE "+SQL.T_FAVORITE+" ADD COLUMN deleted VARCHAR"; db.execSQL(sql1); } }
建立資料庫版本v.3
/** * 作者：created by meixi * 郵箱：[email protected] * 日期：2018/10/9 17 */ public class DBHelper3 extends SQLiteOpenHelper { private static final String DATABASE_NAME = "mall.db"; private static final int DATABASE_VERSION = 1002; private static DBHelper3 instance = null; public DBHelper3(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } public synchronized static DBHelper3 getInstance(Context context) { if (instance == null) { instance = new DBHelper3(context); } return instance; } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(SQL.CREATE_TABLE_FAVORITE); // 若不是第一個版本安裝，直接執行資料庫升級 // 請不要修改FIRST_DATABASE_VERSION的值，其為第一個資料庫版本大小 final int FIRST_DATABASE_VERSION = 1000; onUpgrade(db, FIRST_DATABASE_VERSION, DATABASE_VERSION); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // 使用for實現跨版本升級資料庫 for (int i = oldVersion; i < newVersion; i++) { switch (i) { case 1000: upgradeToVersion1001(db); break; case 1001: upgradeToVersion1002(db); break; default: break; } } } private void upgradeToVersion1001(SQLiteDatabase db){ // favorite表新增1個欄位 String sql1 = "ALTER TABLE "+SQL.T_FAVORITE+" ADD COLUMN deleted VARCHAR"; db.execSQL(sql1); } private void upgradeToVersion1002(SQLiteDatabase db){ // favorite表新增2個欄位,新增新欄位只能一個欄位一個欄位加，sqlite有限制不予許一條語句加多個欄位 String sql1 = "ALTER TABLE "+SQL.T_FAVORITE+" ADD COLUMN message VARCHAR"; String sql2 = "ALTER TABLE "+SQL.T_FAVORITE+" ADD COLUMN type VARCHAR"; db.execSQL(sql1); db.execSQL(sql2); } }
建立資料庫語句：
public class SQL {
public static final String T_FAVORITE = "favorite";
public static final String CREATE_TABLE_FAVORITE =
"CREATE TABLE IF NOT EXISTS " + T_FAVORITE + "(" +
"_id integer primary key autoincrement, " +
"title VARCHAR, " +
"url VARCHAR, " +
"createDate VARCHAR " +
")";
}實現增刪改查activity：
public class MainActivity extends AppCompatActivity {
private static String CREATE_TABLE ="create table number(_id integer primary key autoincrement ,phone real)";
int ab = 0,cd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button1=findViewById(R.id.baocunid);
Button button2=findViewById(R.id.duquid);
Button button3=findViewById(R.id.shanchuid);
Button button4=findViewById(R.id.xiugaiid);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
ab++;
boolean nn = baocun(MainActivity.this, new String[] { "114499title","rullll---htt;s=="+ab,"加入的xxx" });
Log.i("lgq","sbbbb---"+nn);
}
});
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
getBai(MainActivity.this);
}
});
button3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String ss= Delete(MainActivity.this,"1");
Log.i("lgq","shanchu=g==="+ss);
}
});
button4.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String ss = updata(MainActivity.this,"");
Log.i("lgq","xiugg=g==="+ss);
}
});
}
public static boolean baocun(Context context, String[] values) {
SQLiteDatabase db2=null;
DBHelper2 dbHelper = null;
try {
dbHelper =new DBHelper2(context);
db2 = dbHelper.getWritableDatabase();
db2=dbHelper.getWritableDatabase();
db2.beginTransaction();
db2.execSQL("insert into favorite (title,url,deleted) values (?,?,?)",values);
db2.setTransactionSuccessful();
db2.endTransaction();
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}finally{
}
}
public List<String> getBai(Context context){
List<String> list = new ArrayList<String>();
SQLiteDatabase db2=null;
DBHelper2 dbHelper = null;
try {
dbHelper= new DBHelper2(context);
db2=dbHelper.getWritableDatabase();
Cursor cursor =db2.rawQuery("select _id,title,deleted from favorite", null);
while(cursor.moveToNext()){
cd++;
// int dbid = cursor.getInt(cursor.getColumnIndex("_id"));
int id=cursor.getInt(cursor.getColumnIndex("_id"));
String haoma = cursor.getString(cursor.getColumnIndex("title"))+"";
String names = cursor.getString(cursor.getColumnIndex("deleted"));
list.add(haoma);
System.out.println("lgqs======"+haoma+"......."+names+" "+cd+" id=== "+id);
}
db2.setTransactionSuccessful();
db2.endTransaction();
} catch (Exception e) {
e.printStackTrace();
}
return list;
}
public static String Delete(Context context,String string){
SQLiteDatabase db2=null;
DBHelper2 dbHelper = null;
try {
dbHelper =new DBHelper2(context);
db2 = dbHelper.getWritableDatabase();
db2=dbHelper.getWritableDatabase();
db2.beginTransaction();
db2.execSQL("delete from favorite where _id=?",new String[] { string });
db2.setTransactionSuccessful();
db2.endTransaction();
return "成功";
} catch (Exception e) {
e.printStackTrace();
return "失敗";
}
}
public static String updata(Context context,String string){
SQLiteDatabase db2=null;
DBHelper2 dbHelper = null;
try {
dbHelper =new DBHelper2(context);
db2 = dbHelper.getWritableDatabase();
db2=dbHelper.getWritableDatabase();
db2.beginTransaction();
db2.execSQL("update favorite set title ="+"2222999"+" where url =?",new String[]{"rullll---htt;s==3"});
db2.setTransactionSuccessful();
db2.endTransaction();
return "成功";
} catch (Exception e) {
e.printStackTrace();
return "失敗";
}
}
}