how to update indexeddb store items with dexie

Question

I have Indexed db table

    "00014381104394"    
{id: "00014381104394", name: "A House Divided: Season 1 (DVD)", productimg: "http://i5.walmartimages.com/asr/99cfec5c-634e-4e26…4465.jpeg?odnHeight=180&odnWidth=180&odnBg=ffffff", unitofissue: "each", quantity: 1, …}
1   "00016500590958"    
{id: "00016500590958", name: "One A Day Men's 50+ Mini Gels, Multivitamins for Men, 80 Ct", productimg: "http://i5.walmartimages.com/asr/7d44d419-bd6f-4808…b7ea.jpeg?odnHeight=180&odnWidth=180&odnBg=ffffff", unitofissue: "each", quantity: 1, …}
2   "00022141041599"    
{id: "00022141041599", name: "Mepps Dressed Aglia Inline Spinner, Silver & Gray, 1/4 oz", productimg: "http://i5.walmartimages.com/asr/a0ce2579-300a-4536…0d63.jpeg?odnHeight=180&odnWidth=180&odnBg=ffffff", unitofissue: "each", quantity: 1, …}
3   "00038257767124"    
{id: "00038257767124", name: "Hanes Men' Max Cushion Comfort Top B&T Crew Socks 6 Pack", productimg: "http://i5.walmartimages.com/asr/f439dc53-c905-45bb…3436.jpeg?odnHeight=180&odnWidth=180&odnBg=ffffff", unitofissue: "each", quantity: 1, …}
4   "00041333002132"    
{id: "00041333002132", name: "Duracell Coppertop AAA Battery, Long Lasting Triple A Batteries, 24 Pack", productimg: "http://i5.walmartimages.com/asr/09b2aa97-6655-4422…2259d.png?odnHeight=180&odnWidth=180&odnBg=ffffff", unitofissue: "each", quantity: 1, …}
  

i need to update the each item's quantity so I tried the code below

db.cartitems.get(newItemId)
            .then((result) => { 
                 if (result){
                    db.table("cartitems").toArray().then((cartitemArry) => {
                         var cartitemArry1 = []
                        cartitemArry.forEach(product => {
                            if (product.id == newItemId){
    
                                 // increase item quantity
                                var qty = parseInt(product["quantity"])+1
                                product["quantity"] = qty

                                console.log(product.id," was found in cart. Qty increased from ",qty, "to ", product["quantity"])
                                 
                                cartitemArry1.push(product)
                                console.log("cart array push at ",newItemId,"\n", cartitemArry1)


    
                            }else{
                                cartitemArry1.push(product)
                            }
                            console.log("cart array", cartitemArry1)

                            
                        });
                         db.table('cartitems').bulkPut(cartitemArry1)
                            .then(() =>{
                                console.log('finished updating cart')
                            }).catch(error => {
                                console.log(error);
                            });

                       
                        resolve(cartitemArry1)
                     })

The above code fetches all items in table but does not save the updated quantity. I just want to be able to increase or decrease the quantity of a specified itemid. I didn't know how to directly update the property of a specific itemid. So I fetch a desired item and then all items in the store and create a new array with all items in store to include the updated quantity of the desired item and then do a bulkPut to the same store with the new array. – What is the best way to achieve this?

Answer 1

If you just want to increment the "quantity" property of given newItemId in cartitems, do:

db.transaction('rw', db.cartitems, () => {
  return db.cartitems.get(newItemId).then(item => {
    ++item.quantity;
    return db.cartitems.put(item);
  });
});

You could also do this (which is equivalent to the snipped above):

db.cartitems.where({id: newItemId}).modify(item => ++item.quantity);

See docs:

Table.get()

Table.put()

Collection.modify()