Select_or_valuesGenerator.java 文件源码

private static RuleContext rewriteHaving(GeneratorContext ctx, Planner planner, Expr_functionContext rule) {
    String funcname = rule.function_name().getText().toLowerCase();
    if (_aggregates.contains(funcname)) {
        OutputField field = findExisting(ctx, planner, rule);
        if (field != null) {
            return createColumnName_(rule, field);
        }
        else {
            Operator expr = ExprGenerator.gen(ctx, planner, (ExprContext)rule.getParent());
            field = planner.addOutputField("*" + planner.getOutputFields().size(), expr);
            return createColumnName_(rule, field);
        }
    }
    else {
        return rule;
    }
}