// 删除一个表
public void dropTable(String table) {
try {
db.execSQL("drop table if exists " + table);
} catch (SQLException e) {
Toast.makeText(mCtx, "数据表删除失败", Toast.LENGTH_LONG).show();
}
}
public void onPressClear(View view) {
// Do something in response to button
DataBaseHelper databasehelper = new DataBaseHelper(this);
SQLiteDatabase db = databasehelper.getWritableDatabase();
if (db != null) {
// Se elimina la versión anterior de la tabla
db.execSQL("DROP TABLE IF EXISTS " + databasehelper.TABLA);
// Se utiliza para poder crear la nueva base de datos
databasehelper.onCreate(db);
}
}
public void wipeTable(SQLiteDatabase db) {
for (String cmd : DROP_TABLE) {
db.execSQL(cmd);
}
onCreate(db);
}
@Override
public void onCreate(SQLiteDatabase db) {
for (String cmd : CREATE_TABLE) {
db.execSQL(cmd);
}
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS contact");
onCreate(db);
}
public void onCreate(SQLiteDatabase db) {
db.execSQL(
"CREATE TABLE contact ( _id INTEGER PRIMARY KEY AUTOINCREMENT, " + "name TEXT, tel TEXT);");
}
public void createTable(String sql) {
db.execSQL(sql); // 执行有更改的sql语句
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DELETE FROM Topico");
db.execSQL("DELETE FROM Categoria");
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(ScriptSQL.getCreateCategoria());
db.execSQL(ScriptSQL.getCreateTopico());
}