Advanced Lookups are already available for quite some time in Dynamics 365 CE Apps and Model Driven Apps in general. But without Early Access you had and still must activate this feature in the Power Platform Admin Center -> Your Environment -> Settings -> Behavior page
When Early Access is activated in the environment, you do not need to activate the feature – it is the new standard!
You can still configure the Advanced Lookup behavior. Especially for performance reasons it is helpful to set some values inside the lookup behavior options e.g., Set the Minimum number of characters to four, so that the lookup will not start filtering the results directly when starting typing. In addition, setting a delay between characters allows you to continue typing before the results start to appear even though you have reached the previously defined four characters.
If I remember a similar feature in Canvas apps correct, directly filtering the results without delay will increase the API calls -> therefore this might be the case with the Advanced Lookup as well and you should improve the advanced lookup by setting up these values.
But how does the Advanced Lookup work and where do you find it?
First let’s have a look at the normal lookup behavior. And even in the classic lookup the new features have an impact. If you start typing in the classical lookup, initially nothing will happen, as the minimum number of characters has been set to 4. When four characters have been entered and then the input will be slow, then the results will be filtered to the four characters already typed in the lookup.
And where do we find the Advanced Lookup?
If you have opened the Lookup, just have a look to the bottom right of the menu that is shown when clicking on the lookup.
After clicking on this option, the advanced lookup will appear and a pop-up window is shown in front of the current active record.
In this pop-up window it is possible to search, filter and even create new records, without losing the context to the current record in the background. And as we have seen it before in the classic lookup, also in the advanced lookup the delay and the minimum number of characters is working.