如何删除所有记录表在 sqlite 与 Android？

小开

SQLite 不支持 TRUNCATE命令:

DELETE FROM `TABLE_NAME`;

附言。您可以通过对指定数据库的所有查询使用相同的数据库连接实例来优化程序，而不必为每个查询创建一个新的数据库连接实例。

小开

最佳答案

你漏了一个空格: db.execSQL("delete * from " + TABLE_NAME);

此外，甚至不需要包括 *，正确的查询是:

db.execSQL("delete from "+ TABLE_NAME);

小开

要删除表中的所有行，可以使用:

db.delete(TABLE_NAME, null, null);

小开

尝试此代码删除表中的所有数据. 。

String selectQuery = "DELETE FROM table_name ";
Cursor cursor = data1.getReadableDatabase().rawQuery(selectQuery, null);

小开

db.delete(TABLE_NAME, null, null);

或者，如果希望函数返回 已删除行的计数,

db.delete(TABLE_NAME, "1", null);

根据 SQLiteDatabase 删除方法的文档:

要删除所有行并获取计数，请将“1”作为 where 子句。

小开

没有必要使用“执行”函数。下面的代码对我很有用: :

    db.delete(TABLE_NAME,null,null);
db.close();

小开

SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("DELETE FROM tablename"); //delete all rows in a table
db.close();

这对我有用:)

小开

使用带有最后两个空参数的 Sqlit delete 函数。

db.delete(TABLE_NAME,null,null)

小开

    getContentResolver().delete(DB.TableName.CONTENT_URI, null, null);

小开

我用这门课来处理数据库，希望对将来有所帮助。

编程愉快。

public class Database {


private static class DBHelper extends SQLiteOpenHelper {


/**
* Database name
*/
private static final String DB_NAME = "db_name";


/**
* Table Names
*/
public static final String TABLE_CART = "DB_CART";




/**
*  Cart Table Columns
*/
public static final String CART_ID_PK = "_id";// Primary key


public static final String CART_DISH_NAME = "dish_name";
public static final String CART_DISH_ID = "menu_item_id";
public static final String CART_DISH_QTY = "dish_qty";
public static final String CART_DISH_PRICE = "dish_price";


/**
* String to create reservation tabs table
*/
private final String CREATE_TABLE_CART = "CREATE TABLE IF NOT EXISTS "
+ TABLE_CART + " ( "
+ CART_ID_PK + " INTEGER PRIMARY KEY, "
+ CART_DISH_NAME + " TEXT , "
+ CART_DISH_ID + " TEXT , "
+ CART_DISH_QTY + " TEXT , "
+ CART_DISH_PRICE + " TEXT);";




public DBHelper(Context context) {
super(context, DB_NAME, null, 2);


}


@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_TABLE_CART);




}


@Override
public void onUpgrade(SQLiteDatabase db, int arg1, int arg2) {
db.execSQL("DROP TABLE IF EXISTS " + CREATE_TABLE_CART);
onCreate(db);
}


}




/**
* CART handler
*/
public static class Cart {




/**
* Check if Cart is available or not
*
* @param context
* @return
*/
public static boolean isCartAvailable(Context context) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();
boolean exists = false;


try {
String query = "SELECT * FROM " + DBHelper.TABLE_CART;
Cursor cursor = db.rawQuery(query, null);
exists = (cursor.getCount() > 0);
cursor.close();
db.close();
} catch (SQLiteException e) {
db.close();
}


return exists;
}




/**
* Insert values in cart table
*
* @param context
* @param dishName
* @param dishPrice
* @param dishQty
* @return
*/
public static boolean insertItem(Context context, String itemId, String dishName, String dishPrice, String dishQty) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(DBHelper.CART_DISH_ID, "" + itemId);
values.put(DBHelper.CART_DISH_NAME, "" + dishName);
values.put(DBHelper.CART_DISH_PRICE, "" + dishPrice);
values.put(DBHelper.CART_DISH_QTY, "" + dishQty);


try {
db.insert(DBHelper.TABLE_CART, null, values);
db.close();
return true;
} catch (SQLiteException e) {
db.close();
return false;
}
}


/**
* Check for specific record by name
*
* @param context
* @param dishName
* @return
*/
public static boolean isItemAvailable(Context context, String dishName) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();
boolean exists = false;


String query = "SELECT * FROM " + DBHelper.TABLE_CART + " WHERE "
+ DBHelper.CART_DISH_NAME + " = '" + String.valueOf(dishName) + "'";




try {
Cursor cursor = db.rawQuery(query, null);


exists = (cursor.getCount() > 0);
cursor.close();


} catch (SQLiteException e) {


e.printStackTrace();
db.close();


}


return exists;
}


/**
* Update cart item by item name
*
* @param context
* @param dishName
* @param dishPrice
* @param dishQty
* @return
*/
public static boolean updateItem(Context context, String itemId, String dishName, String dishPrice, String dishQty) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(DBHelper.CART_DISH_ID, itemId);
values.put(DBHelper.CART_DISH_NAME, dishName);
values.put(DBHelper.CART_DISH_PRICE, dishPrice);
values.put(DBHelper.CART_DISH_QTY, dishQty);


try {


String[] args = new String[]{dishName};
db.update(DBHelper.TABLE_CART, values, DBHelper.CART_DISH_NAME + "=?", args);


db.close();




return true;
} catch (SQLiteException e) {
db.close();


return false;
}
}


/**
* Get cart list
*
* @param context
* @return
*/
public static ArrayList<CartModel> getCartList(Context context) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();


ArrayList<CartModel> cartList = new ArrayList<>();


try {
String query = "SELECT * FROM " + DBHelper.TABLE_CART + ";";


Cursor cursor = db.rawQuery(query, null);




for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()) {


cartList.add(new CartModel(
cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_ID)),
cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_NAME)),
cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_QTY)),
Integer.parseInt(cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_PRICE)))
));
}


db.close();


} catch (SQLiteException e) {
db.close();
}
return cartList;
}


/**
* Get total amount of cart items
*
* @param context
* @return
*/
public static String getTotalAmount(Context context) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();


double totalAmount = 0.0;


try {
String query = "SELECT * FROM " + DBHelper.TABLE_CART + ";";


Cursor cursor = db.rawQuery(query, null);




for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()) {


totalAmount = totalAmount + Double.parseDouble(cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_PRICE))) *
Double.parseDouble(cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_QTY)));
}


db.close();




} catch (SQLiteException e) {
db.close();
}




if (totalAmount == 0.0)
return "";
else
return "" + totalAmount;
}




/**
* Get item quantity
*
* @param context
* @param dishName
* @return
*/
public static String getItemQty(Context context, String dishName) {


DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();


Cursor cursor = null;
String query = "SELECT * FROM " + DBHelper.TABLE_CART + " WHERE " + DBHelper.CART_DISH_NAME + " = '" + dishName + "';";
String quantity = "0";


try {
cursor = db.rawQuery(query, null);


if (cursor.getCount() > 0) {


cursor.moveToFirst();
quantity = cursor.getString(cursor
.getColumnIndex(DBHelper.CART_DISH_QTY));


return quantity;
}




} catch (SQLiteException e) {
e.printStackTrace();
}


return quantity;
}




/**
* Delete cart item by name
*
* @param context
* @param dishName
*/
public static void deleteCartItem(Context context, String dishName) {
DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();


try {


String[] args = new String[]{dishName};
db.delete(DBHelper.TABLE_CART, DBHelper.CART_DISH_NAME + "=?", args);


db.close();
} catch (SQLiteException e) {
db.close();
e.printStackTrace();
}


}




}//End of cart class


/**
* Delete database table
*
* @param context
*/
public static void deleteCart(Context context) {
DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase();


try {


db.execSQL("DELETE FROM " + DBHelper.TABLE_CART);


} catch (SQLiteException e) {
e.printStackTrace();
}


}

}

用法:

  if(Database.Cart.isCartAvailable(context)){


Database.deleteCart(context);


}

小开

写就是了

SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("delete from "+TableName);

或者

db.delete(tablename,null,null);

小开

可能是有用的

public boolean deleteAllFood() { SQLiteDatabase db = dbHelper.getReadableDatabase(); int affectedRows = db.delete(DBHelper.TABLE_NAME_FOOD, null, null); return affectedRows > 0; } public class DBProgram { private static DBProgram INSTANCE; private Context context; private DBHelper dbHelper; private DBProgram(Context context) { // burda bu methodu kullanan activity ile eileştiriyoruz this.dbHelper = new DBHelper(context); } public static synchronized DBProgram getInstance(Context context) { if (INSTANCE == null) { INSTANCE = new DBProgram(context); } return INSTANCE; } //********************************************** public boolean updateById(ProgramModel program) { SQLiteDatabase database = dbHelper.getWritableDatabase(); ContentValues contentValues = new ContentValues(); contentValues.put(DBHelper.COLUM_NAME_P, program.getProgName()); contentValues.put(DBHelper.COLUM_DAY_P, program.getDay()); contentValues.put(DBHelper.COLUMN_WEIGHT_P, program.getWeight()); contentValues.put(DBHelper.COLUMN_SET_P, program.getSet()); contentValues.put(DBHelper.COLUMN_REPETITION_P, program.getRepetition()); int affectedRows = database.update(DBHelper.TABLE_NAME_PROGRAM, contentValues, "PROG_ID_P = ?", new String[]{String.valueOf(program.getId())}); return affectedRows > 0; } //********************************************** //********************************************** // TODO public boolean deleteProgramById(int id) { SQLiteDatabase database = dbHelper.getReadableDatabase(); int affectedRows = database.delete(DBHelper.TABLE_NAME_PROGRAM, DBHelper.COLUMN_ID_P + "= ?", new String[]{String.valueOf(id)}); // return bize etkilenen sıra sayısınıını temsil eder return affectedRows > 0; } //********************************************** //*************************************************** public boolean deleteProgramByName(String progName) { SQLiteDatabase database = dbHelper.getReadableDatabase(); final String whereClause = DBHelper.COLUM_NAME_P + "=?"; final String whereArgs[] = {progName}; int affectedRows = database.delete(DBHelper.TABLE_NAME_PROGRAM, whereClause, whereArgs); return affectedRows > 0; } //*************************************************** //************************************** get Meal // TODO WEB Get All Meals public List<ProgramModel> getAllProgram(String name) { List<ProgramModel> foodList = new ArrayList<>(); ProgramModel food; SQLiteDatabase database = dbHelper.getReadableDatabase(); final String kolonlar[] = {DBHelper.COLUMN_ID_P, DBHelper.COLUM_NAME_P, DBHelper.COLUM_DAY_P, DBHelper.COLUMN_WEIGHT_P, DBHelper.COLUMN_SET_P, DBHelper.COLUMN_REPETITION_P}; final String whereClause = DBHelper.COLUM_DAY_P + "=?"; final String whereArgs[] = {name}; Cursor cursor = database.query(DBHelper.TABLE_NAME_PROGRAM, kolonlar, whereClause, whereArgs, null, null, null); while (cursor.moveToNext()) { food = new ProgramModel(); food.setId(cursor.getInt(cursor.getColumnIndex(DBHelper.COLUMN_ID_P))); food.setProgName(cursor.getString(cursor.getColumnIndex(DBHelper.COLUM_NAME_P))); food.setDay(cursor.getString(cursor.getColumnIndex(DBHelper.COLUM_DAY_P))); food.setWeight(cursor.getInt(cursor.getColumnIndex(DBHelper.COLUMN_WEIGHT_P))); food.setSet(cursor.getInt(cursor.getColumnIndex(DBHelper.COLUMN_SET_P))); food.setRepetition(cursor.getInt(cursor.getColumnIndex(DBHelper.COLUMN_REPETITION_P))); foodList.add(food); } database.close(); cursor.close(); return foodList; } //************************************** //**************************************insert FOOD //TODO LOCAL insert Foods public boolean insertProgram(ProgramModel favorite) { boolean result = false; ContentValues contentValues = new ContentValues(); contentValues.put(DBHelper.COLUM_NAME_P, favorite.getProgName()); contentValues.put(DBHelper.COLUM_DAY_P, favorite.getDay()); contentValues.put(DBHelper.COLUMN_WEIGHT_P, favorite.getWeight()); contentValues.put(DBHelper.COLUMN_SET_P, favorite.getSet()); contentValues.put(DBHelper.COLUMN_REPETITION_P, favorite.getRepetition()); SQLiteDatabase database = dbHelper.getWritableDatabase(); long id = database.insert(DBHelper.TABLE_NAME_PROGRAM, null, contentValues); if (id != 1) { result = true; } database.close(); return result; } //*************************************************** // ******************************* SQLITE HELPER CLASS ****************** private class DBHelper extends SQLiteOpenHelper { private final Context context; private static final String DATABASE_NAME = "PROGRAM_INFO"; private static final String TABLE_NAME_PROGRAM = "PROGRAM"; private static final int DATABASE_VERSION = 2; // FOOD private static final String COLUMN_ID_P = "PROG_ID_P"; private static final String COLUM_NAME_P = "PROG_NAME_P"; private static final String COLUM_DAY_P = "PROG_DAY_P"; private static final String COLUMN_WEIGHT_P = "PROG_WEIGHT_P"; private static final String COLUMN_SET_P = "PROG_SET_P"; private static final String COLUMN_REPETITION_P = "PROG_REPETITION_P"; private final String CREATE_TABLE_PROGRAM = "CREATE TABLE " + TABLE_NAME_PROGRAM + " (" + COLUMN_ID_P + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COLUM_NAME_P + " TEXT, " + COLUM_DAY_P + " TEXT, " + COLUMN_WEIGHT_P + " INTEGER, " + COLUMN_SET_P + " INTEGER, " + COLUMN_REPETITION_P + " INTEGER)"; private static final String DROP_TABLE_PROGRAM = "DROP TABLE IF EXIST " + TABLE_NAME_PROGRAM; public DBHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); this.context = context; } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_TABLE_PROGRAM); Util.showMessage(context, "Database Created"); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { db.execSQL(DROP_TABLE_PROGRAM); Util.showMessage(context, "Database Upgrated"); onCreate(db); } @Override public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) { super.onDowngrade(db, oldVersion, newVersion); } } }

小开

此方法从数据库中删除所有数据

public void deleteAll() { SQLiteDatabase db = this.getWritableDatabase(); db.execSQL("delete from "+ TABLE_NAME); db.close(); }

小开

//Delete all records of table db.execSQL("DELETE FROM " + TABLE_NAME); //Reset the auto_increment primary key if you needed db.execSQL("UPDATE SQLITE_SEQUENCE SET SEQ=0 WHERE NAME=" + TABLE_NAME); //For go back free space by shrinking sqlite file db.execSQL("VACUUM");

小开

这对我有用。这里的区别在于 ExecSQL 和 rawQuery。RawQuery 主要用于搜索 case，而 ExecSQL 主要用于 application 操作。

// truncate the table ArrayList<HashMap<String, String>> getDatabaseName1(String sr) { SQLiteDatabase sqLiteDatabase=this.getWritableDatabase(); sqLiteDatabase.execSQL("delete from Hotel"); sqLiteDatabase.close(); return null; }

小开

我有一个功能，为我在 Unity (与数据库 SQLite 结合)。

代码 C # :

public void DeleteAllObj() { connectionString = "URI=file:"+Application.dataPath+"/TerrainTools/db/object.sqlite"; using (IDbConnection dbConnection = new SqliteConnection(connectionString)) { dbConnection.Open(); using(IDbCommand dbCmd =dbConnection.CreateCommand()) { dbCmd.CommandText = "DELETE FROM 'ObjectMap'"; using (IDataReader reader = dbCmd.ExecuteReader()) { dbConnection.Close(); reader.Close(); return; } } } }

小开

这里有一个简单的删除方法:

public void deleteItem(Item item) { SQLiteDatabase db = getWritableDatabase(); String whereClause = "id=?"; String whereArgs[] = {item.id.toString()}; db.delete("Items", whereClause, whereArgs); }

这里 whereClause是可选的，传递 null 将删除表中的所有行。如果 whereClause通过，delete 函数将返回受影响的行数，否则返回0。

重要提示: 如果您想删除所有的行，并且需要删除行的计数，那么将1作为 whereClause传递。

小开

您可以在 sqlite android 中使用两种不同的方法来删除或任何查询

第一种方法是

public void deleteItem(Student item) { SQLiteDatabase db = getWritableDatabase(); String whereClause = "id=?"; String whereArgs[] = {item.id.toString()}; db.delete("Items", whereClause, whereArgs); }

第二种方法

public void deleteAll() { SQLiteDatabase db = this.getWritableDatabase(); db.execSQL("delete from "+ TABLE_NAME); db.close(); }

为你的用例使用任何方法

小开

在 VStudio 中使用 SQLite _ NET _ PCL v1.6.292——许多文档和注释似乎已经过时了(我认为)。

删除所有记录

public Task<int> DeleteAllEntry() { return DataBasePath.DeleteAllAsync<tableName>(); }

小开

截断 SQLite 表? ？

截断答案不正确。 在 SQLite 中，它通过2个查询实现;

1. db.execSQL("delete from "+ TABLE_NAME); 2. db.execSQL("UPDATE SQLITE_SEQUENCE SET seq = 0 WHERE name = '"+ TABLE_NAME+"'");

记住第2个查询 中的单引号;

那么为什么这两个问题呢？

观察所询问了 Trucate 的情况。

这意味着删除所有记录，并将该表的自动递增值设置为0

这就是我们在这里所做的。(截断命令在 SQLite 中不可用[直到日期回复发布])