CreateQuery t_sparse_full (children 3) Identifier t_sparse_full Columns definition (children 1) ExpressionList (children 3) ColumnDeclaration id (children 1) DataType UInt64 ColumnDeclaration u (children 1) DataType UInt64 ColumnDeclaration s (children 1) DataType String Storage definition (children 3) Function MergeTree Identifier id Set