MySql updating column that is null -


i trying update column value has null value.

table:

+------------+-----------+-------+ | product_no | name      | price | +------------+-----------+-------+ |          1 | cheese    |  9.99 | |       null | meat      | 17.00 | |          2 | pepperoni |  null | +------------+-----------+-------+

update:

update products set product_no = 6 product_no = null;

output:

query ok, 0 rows affected (0.00 sec) rows matched: 0  changed: 0  warnings: 0

table definition:

+------------+---------------+------+-----+---------+-------+ | field      | type          | null | key | default | | +------------+---------------+------+-----+---------+-------+ | product_no | int(11)       | yes  |     | null    |       | | name       | varchar(255)  | yes  |     | null    |       | | price      | decimal(10,2) | yes  |     | null    |       | +------------+---------------+------+-----+---------+-------+

why not updating 6?

try this:

update products set product_no = 6 product_no null;

Comments

Post a Comment

Popular posts from this blog

user interface - how to replace an ongoing process of image capture from another process call over the same ImageLabel in python's GUI TKinter -

i trying use following code create interactive gui changes color-space(hsv, rbg, grayscale etc) on event of button click. display opencv video in tkinter using multiprocessing being new python having problems multiprocessing , attempts on making gui change it's color space on button clicks hangs entire system. on it's implementation highly appreciated. thankyou. below code: import cv2 pil import image,imagetk import tkinter tk import numpy np multiprocessing import process , queue def quit_it(root,process): root.destroy() process.terminate() def black_andwhite(root,process): process.terminate p=process(target=capture_image, args=(5,queue, )) p.start() root.after(0, func=lambda: update_all(root, image_label, queue)) def update_image(image_label, queue): frame = queue.get() = image.fromarray(frame) b = imagetk.photoimage(image=a) image_label.configure(image=b) image_label._image_cache = b root.update() def update_all(root...
Read more

javascript - Using jquery append to add option values into a select element not working -

i'm looking dynamically populate select element names of items stored array. for reason it's not working , i'm not sure why. html: <div class="col-md-4 col-md-offset-4"> <select class="select1"> </select> , <select class="select2"> </select> </div> note i'm using bootstrap layout. here's jquery i'm using try , populate ".select1" jquery: select: function() { $.each(state.greens, function(index, value) { $(".select1").append("<option value =' " + index + " '>" + state.greens[index].name + "</option>"); }); } note function 'select' stored within object called 'display'. state.greens name of array i'm trying access. so @ end of html page call display.select(); call function. no error messages showing in console. also, saw question: appending ...
Read more

javascript - Restarting Supervisor and effect on FlaskSocketIO -

in index.html (html/javascript) have: $(document).ready(function(){ namespace = '/test'; var socket = io.connect('http://' + document.domain + ':' + location.port + namespace); socket.on('connect', function() { socket.emit('join', {room: 'venue_1'}); }); socket.on('my response', function(msg) { $('#log').append('<br>received #' + ': ' + msg.data); }); }); on server have: @socketio.on('connect', namespace='/test') def test_connect(): if session.get('venue_id'): emit('my response', {'data': 'connected'}) session.pop('venue_id', none) else: request.namespace.disconnect() @socketio.on('join', namespace='/test') def join(message): join_room(message['room']) room = message[...
Read more