Package org.apache.calcite.rex

Class RexFieldAccess

  • public class RexFieldAccess
extends RexNode
    Access to a field of a row-expression.

    You might expect to use a RexFieldAccess to access columns of relational tables, for example, the expression emp.empno in the query 

    SELECT emp.empno FROM emp

    but there is a specialized expression RexInputRef for this purpose. So in practice, RexFieldAccess is usually used to access fields of correlating variables, for example the expression emp.deptno in 

    SELECT ename
 FROM dept
 WHERE EXISTS (
     SELECT NULL
     FROM emp
     WHERE emp.deptno = dept.deptno
     AND gender = 'F')