Query for unique item in list

Question

I have an SP list of items, each item has a unique Title. I would like to use the title as my way to find and then update that row of data. I thought the below code would find only the item that has a Title = "Apptest" but it always gives me all items in the list and all of them are updated. I get the same results if I remove the ViewXml line, so I think there is something wrong with that line but I can't find it. Before: After:

var list = clientContext.Web.Lists.GetByTitle("Test");
            var camlQuery = new CamlQuery
            {
                ViewXml = @"<Query><Where><Eq><FieldRef Name='Title' /><Value Type='Text'>Apptest</Value></Eq></Where></Query>"
            };

            var listItems = list.GetItems(camlQuery);
            clientContext.Load(listItems);
            clientContext.ExecuteQuery();

            foreach (var listItem in listItems)
            {
                Console.WriteLine($"{listItem["Title"]}");
                listItem["Title"] = "AppUpdateTest";
                listItem.Update();
                clientContext.ExecuteQuery();
            }

Answer 1

Please have a try to add 'View' around 'Query' like below:

{ ViewXml = "<View><Query><Where><Eq><FieldRef Name='Title' /><Value Type='Text'>xxxxx</Value></Eq></Where></Query></View>"};

Reference docs:

• https://docs.microsoft.com/en-us/previous-versions/office/developer/sharepoint-2010/ee534956(v%3Doffice.14)#retrieving-items-from-a-list