Question

我一直得到一个“通知：未定义的索引：做了”这个查询的错误，我不明白为什么......我更习惯于mysql，所以，也许语法错了？

这是php查询代码：

function get_demos() {
        global $session;
        $demo = array();
        $result = pg_query("SELECT DISTINCT(did,vid,iid,value) FROM dv");
        if(pg_num_rows($result) > 0) {
            while($r = pg_fetch_array($result)) {
                switch($r['did']) {
                    case 1:
                        $demo['a'][$r['vid']] = $r['value'];
                        break;
                    case 2:
                        $demo['b'][$r['vid']] = $r['value'];
                        break;
                    case 3:
                        $demo['c'][$r['vid']] = $r['value'];
                        break;
                }
            }
        } else {
            $session->session_setMessage(2);
        }

        return $demo;
    }

当我在pg提示符下运行该查询时，我得到了结果：

"(1,1,1,"A")"
"(1,2,2,"B")"
"(1,3,3,"C")"
"(1,4,4,"D")"
"(1,5,5,"E")"
"(1,6,6,"F")"
"(1,7,7,"G")"
"(1,8,8,"H")"
"(1,9,9,"I")"
"(1,10,A,"J")"
"(1,11,B,"K")"
"(1,12,C,"L")"
"(1,13,D,"M")"
"(2,14,1,"A")"
"(2,15,2,"B")"
"(2,16,0,"C")"
"(3,17,1,"A")"
"(3,18,2,"B")"
"(3,19,3,"C")"
"(3,20,4,"D")"
"(3,21,5,"E")"
"(3,22,6,"F")"
"(3,23,7,"G")"

Answer 1

如果要在$ r中获取关联数组，则必须使用pg_fetch_assoc()函数。

postgresql帮助php循环

1 个答案: