CreateQuery table_with_single_pk (children 3)
 Identifier table_with_single_pk
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration key (children 1)
    DataType UInt8
   ColumnDeclaration value (children 1)
    DataType String
 Storage definition (children 3)
  Function MergeTree
  Identifier key
  Set
