How can I reinsert a row using SQLAlchemy?

Question

To add the item with the given description I use: db.session.add(new_item). To delete the item: db.session.query(Item).filter_by(item_id=new_id).delete(). To update some parts of the item: db.session.query(Item).filter_by(item_id=new_id).update({"status":"1 "}).

What should I use if I want to edit the item completely, that is, reinsert the data for the same item?

here is the code for the form:

        <form class="form" action="{{ url_for('new_item') }}" method="post" role="form" enctype=multipart/form-data>
      {{ form.csrf_token }}
      <table>
        <tr>
          <td>
            <div class="form-group">
              <label for="item_name">item name:</label>
              <input name="name" type="text" class="form-control" id="item_name">
            </div>
            </td>
          <td>
            <div class="form-group">
              <label for="item_price">item price</label>
              <input name="price" type="number" class="form-control" id="item_price">
            </div>
          </td>

          <td>
            <div class="form-group">
              <label for="photo">Download the photo</label>
              <input type="file" name="file">
              <p class="help-block">Download</p>
            </div>
          </td>
        </tr>
        <tr>

          <td>
            <div class="form-group">
              <label for="item_category">Category:</label>
              <select name="category" class="form-control" id="item_category">
                <option>LEGO</option>
                <option>Игры_и_игрушки</option>
                <option>Малыш</option>
                <option>Школа_и_канцтовары</option>
                <option>Творчество_и_развитие</option>
              </select>
            </div>
          </td>
        </tr>
      </table>


      <div class="form-group">
        <label for="item_description">Description of the item:</label>
        <textarea name="description" class="form-control" id="item_description" rows="3"></textarea>
      </div>
      <button type="submit" class="btn btn-default">Save</button>


    </form>

Here is the route for the form. There are others as well, to update the items and to delete it, but i guess this should be enough

@app.route('/admin_items', methods=['GET', 'POST'])
def admin_items():
    form = AddItemForm(request.form)
    available = db.session.query(Item).filter_by(status='1').order_by(Item.name.asc())
    not_available = db.session.query(Item).filter_by(status='0').order_by(Item.name.asc())
    return render_template('admin_items.html',
                            available_items=available,
                            not_available_items=not_available,
                            form=form)

@app.route('/add_item', methods=['GET', 'POST'])
@login_required
def new_item():
    error = None
    form = AddItemForm(request.form)
    if request.method == 'POST':
        file = request.files['file']
        if file and allowed_file(file.filename) and form.name.data != "" and form.description.data != "":
            filename = secure_filename(file.filename)
            file.save(os.path.join(app.config['UPLOADED_ITEMS_DEST'], filename))
            new_item = Item(
                filename,
                form.name.data,
                form.description.data,
                form.price.data,
                form.age.data,
                form.particles.data,
                form.category.data,
                '1',
                )
            db.session.add(new_item)
            db.session.commit()
            return redirect(url_for('admin_items'))
        else:
            return render_template('admin_items.html', form=form, error=error)
    if request.method == 'GET':
        return redirect(url_for('admin_items'))

Answer 1

You can specify more elements to the update clause .update({"status":"1", "colour":"red"}) or you can grab the object from the database and just change it as required:

item = db.session.query(Item).get(1) # grab the item with PK #1.
item.status = '1'
item.colour = 'red'
db.session.commit() # commit your changes to the database.