SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 3) ExpressionList (children 1) Function equals (children 1) ExpressionList (children 2) Literal UInt64_3 Function positionCaseInsensitive (children 1) ExpressionList (children 2) Function materialize (children 1) ExpressionList (children 1) Literal \'abc\' Literal \'C\' TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier system.numbers Literal UInt64_10