[00:00] In this video, we are going to look at using named queries on perspective components. I'm going to be using some of the named queries and the table that was created in the sequel basics Inductive University topic. If you want to follow along, you can download the queries from the Ignition Exchange. Now in this perspective view, I'm going to add a table component. The first thing we will take a look at is using a named query in a binding. I'm going to set up a binding on the data property of the table and select the query binding type. Here we can select the path to the query that we want to run. I'll use the query select. As you may recall, this query selects all data from our inventory table. We see the query here and can turn on polling or having the query automatically rerun to get updates to the data here.

[01:08] Polling occurs on a timer which you can adjust to meet how often you want to get updated data. It can even take an expression which allows you to define the polling rate based on an expression. After clicking okay, we can see our data in the table. Next, let's look at running a named query from a script. I'm going to add a button to run my script, go to its action performed event and add a script action. Here I am going to call a system function, system.db.runNamedQuery which we can pass the path of the query we want to run as a string. I'm going to call the query update inventory. This will run the update query which will change the quantity of the workstations in support from 22 to 23.

[02:09] However, because I did not set the binding on my table to pull, my table component will not reflect the change until the query is rerun, usually when the view is navigated to. So in a script where we update data in the database, it is usually a good idea to refresh any bindings that are selecting that data out. To do this, we need to grab the table component and call refresh binding on it, passing in the property that we want to refresh as a string which in this case is props.data. Testing this out, we can see that the quantity does indeed change from 22 to 23. Next, let's take a look at named queries that use parameters.

[03:06] I'll start by adding a text field to the view and then opening up the binding on my table again. I want to change the query that is being run from select to filtered select. The filtered select allows us to pull data out of the table, but only rows that match a name we provide will be returned. You will notice now, not only do we see the query, but the query accepts a parameter which we can provide a value for up above here. I can type in a static value or I can click on the function symbol on the right which will let me create an expression that will result in a value instead. I'm simply going to grab the text property of my text field. When I hit okay, you will notice all of the data disappears. This is because it is currently looking for a name that is simply an empty string because that is all I have in my text field.

[04:08] Of course I don't have any blank names in my table so let's type a name into my text field. As you can see, as soon as the value was entered, the query returned the appropriate data. Finally, let's take a look at using a query with parameters in a script. I'm going to add another button and another table to my view. I will add a script action to the action performed event just as before. Here, I will again add the system function system.db.runNamedQuery and call the query filtered select. In addition to the path to the query, I also need to specify any parameters that should be passed into the query in the form of a dictionary.

[05:05] I just have the one parameter called name. So I will create a dictionary entry called name and provide it with the text value from my text field. I then need to put the return data into the second table since I did not set up any bindings. I will store the return data in a variable and then set my table data equal to the data in the variable. Unlike the binding, the script will not run until I execute it by pressing the button regardless of if I change the name in the text field. However, clicking the button will pull in the text value of the text field to use as a parameter in the named query.