As you know a normal split method is accepting only a character . It will throw an error when we give a string to split. This code shows you how you can use split method to split a string by a string in c#.
[csharp]
string myQuery="select * from tblAccount where id=1"
List<string> queryList = myQuery.Split(new string[] { "where" }, StringSplitOptions.None).ToList();
[/csharp]
The queryList will give you the list after split

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