Here we will see how to add a query on a table in LightSwitch using Visual Studio 2012.
This article describes how to add a query in a table.
Step 1
Open the Solution Explorer.
![Query sol exp.jpg]()
Step 2
In the Solution Explorer, right-click on the Server and choose "Add Table".
![Add table.jpg]()
Step 3
The table appears.
![emp.jpg]()
Step 4
In the Solution Explorer, right-click on the Screens and choose "Add Screen".
![Add Screen.jpg]()
Step 5
The Add New Screen dialog box appears. Select the "Editable Grid Screen" from the Screen Template, under screen information, choose "Employee" under the screen data and provide a name to the Screen and click the "OK" button.
![Screen.jpg]()
The screen designer appears.
![src desi.jpg]()
Step 6
Press F5 to run the application.
![output.jpg]()
Step 7
Now stop debugging and right-click on the table and choose "Add Query".
![Add query.jpg]()
The Query Screen Designer will open. Right-click on the query and choose "Rename" to rename the query.
![rename.jpg]()
Step 8
There are two ways of adding parameters to a Query.
1: Go to "Add Query Element" in the top of the query designer, a drop down list will appear, choose "Add Filter".
![Add filter.jpg]()
2: Another way is, in the query designer, directly click on "Add Filter".
![Or Add Filter.jpg]()
Either way, a new row will be added by which you can add a query.
![filter added.jpg]()
The filter consists of the following 5 columns:
1: The first column consists of two values in a drop down format (in other words where and where not).
![where or where not.jpg]()
2: The second column consists of a list of all the records that belong to a table on which the filter can be applied. The user can select any one field from the given list.
![Address.jpg]()
3: The third column consists of the list of all comparison operators. Here the user can also select an operator from the list.
![equal operator.jpg]()
4: The fourth column consists of the query parameter type.
![literal.jpg]()
5: The fifth column consists of the query parameter value.
![value.jpg]()
To add a parameter, select parameter under the type of query parameter and select "Add New" in the last column.
![Add New.jpg]()
Once we have selected the "Add New" option, in the parameter section a new row will be added automatically as shown below.
![new row in parameter.jpg]()
Suppose we want to make the parameter optional. To do that first select the parameter option and then go to the property window.
![parameter.jpg]()
Mark the "IsOptional" checkbox checked.
![property win.jpg]()