Performance Optimization: Manual Cell Execution

Next, let's move on to manual cell execution. There are two options for this. We can change the setting across your cold canvas or we can do this for specific cells. Here I have some queries running against my database, and perhaps I want to make some edits. And I know that I'm going to be clicking in and out of these as I make edits. And I don't particularly want them to be hitting my database again and again while I do this work. So with nothing selected, I can see in the right hand panel that we have an option to execute cells automatically, and I can turn this off. If, for example, then I edit my query, I'll just add in another column. We will see that we have a warning that this cell has not been executed. It'll tell us roughly how much memory that will take when it does run, and it gives us the option to run it manually. As we know when we change a cell, everything downstream also updates. So we can see now that the two cells downstream also have this message. So we can reverse these. So it can be really useful to just stop everything running in your canvas until you've done the work, and then you can turn it back on again. But we also have the option to toggle this for individual cells. So if I click on my cell in this drop down, I can disable cell execution just for this cell. So now if I come and edit this, we will see that I'm receiving the same message for this cell, but the cells downstream are updating. So this can be useful if you need more granular control and if there's certain cells maybe returning larger results that you would like to toggle off at certain times.