SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 3) ExpressionList (children 1) Function equals (children 1) ExpressionList (children 2) Function concat (children 1) ExpressionList (children 3) Function materialize (children 1) ExpressionList (children 1) Literal \'a\' Literal \'b\' Literal \'c\' Literal \'abc\' TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier system.numbers Literal UInt64_5