CreateQuery test_table (children 3)
 Identifier test_table
 Columns definition (children 1)
  ExpressionList (children 4)
   ColumnDeclaration key (children 1)
    DataType UInt32
   ColumnDeclaration A (children 1)
    DataType Nullable (children 1)
     ExpressionList (children 1)
      DataType UInt32
   ColumnDeclaration B (children 1)
    DataType Nullable (children 1)
     ExpressionList (children 1)
      DataType String
   ColumnDeclaration C (children 1)
    DataType Tuple (children 1)
     ExpressionList (children 1)
      DataType Nullable (children 1)
       ExpressionList (children 1)
        DataType String
 Storage definition (children 2)
  Function CoalescingMergeTree (children 1)
   ExpressionList
  Identifier key
