Walmart's online sales growth has sharply slowed -- and it highlights a key weakness in its battle with Amazon (WMT)

Getty Walmart's online sales grew 23% in the most recent quarter, down from 50% growth in the previous period. The company said it failed to keep some basic items in stock over the holidays, as it tried to manage higher demand of seasonal items like televisions and toys. Walmart's online sales growth sharply slowed over the critical holiday period, falling to 23% growth from a staggering 50% jump in the previous quarter. Walmart CEO Doug McMillon said Tuesday that most of the slowed growth was "...