SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 1) ExpressionList (children 1) Function dateDiff (children 1) ExpressionList (children 3) Literal \'second\' Function materialize (children 1) ExpressionList (children 1) Function toDateTime64 (children 1) ExpressionList (children 3) Literal \'1927-01-01 00:00:00\' Literal UInt64_6 Literal \'UTC\' Function toDateTime64 (children 1) ExpressionList (children 3) Literal \'1927-01-01 00:00:10\' Literal UInt64_3 Literal \'UTC\'