/**
* Adds an expression and returns a reference name. If an alias is given, it specifies the alias
* as an reference name.
*/
public String addNamedExpr(NamedExpr namedExpr) throws PlanningException {
if (namedExpr.hasAlias()) {
return addExpr(namedExpr.getExpr(), namedExpr.getAlias());
} else {
return addExpr(namedExpr.getExpr());
}
}
@Override
public Expr visitColumnReference(
ExprNormalizedResult ctx, Stack<Expr> stack, ColumnReferenceExpr expr)
throws PlanningException {
// normalize column references.
if (!expr.hasQualifier()) {
if (ctx.block.namedExprsMgr.contains(expr.getCanonicalName())) {
NamedExpr namedExpr = ctx.block.namedExprsMgr.getNamedExpr(expr.getCanonicalName());
return new ColumnReferenceExpr(namedExpr.getAlias());
} else {
String normalized = ctx.plan.getNormalizedColumnName(ctx.block, expr);
expr.setName(normalized);
}
}
return expr;
}