CreateQuery t_sparse_pk (children 3) Identifier t_sparse_pk Columns definition (children 1) ExpressionList (children 2) ColumnDeclaration k (children 1) DataType UInt64 ColumnDeclaration v (children 2) DataType UInt64 Function CODEC (children 1) ExpressionList (children 1) Function NONE Storage definition (children 3) Function MergeTree Identifier k Set