CAML query to retrieve a list of users items with ids in a list

Question

I am a beginner in SharePoint using CAML query to get a list of user items from a SharePoint list.

The data I have is a userid list like below:

1 2 3 4 5

Now I want to write a CAML query to retrieve the user items from a SharePoint list where the userid is in (1,2,3,4,5)

Answer 1

If you want to filter data by user ID you need to set LookupId="TRUE" for Author field:

<Eq>
  <FieldRef Name="Author" LookupId="TRUE" />
  <Value Type="Integer">1</Value>
</Eq>

If you want to use multiple values for this field you should check IN Element. So your CAML should look like this:

 <In>
  <FieldRef Name="Author" LookupId="True" />
  <Values>
    <Value Type="Integer">1</Value>
    <Value Type="Integer">2</Value>
    <Value Type="Integer">3</Value>
  </Values>
</In>