Question

如何编写SQL查询以检查列中的每个NAIC代码值是否为3，如果是，则对具有相同3位数NAIC代码的所有输出值求和

SELECT ni.NAICS,
ncio.outputValue,
IF( NAICS =SUBSTR(ni.NAICS,0,3), SUM(ncio.outputValue), NULL )

                            FROM 
                                    nwk_company_industry_output ncio,
                                    nwk_industry ni,
                                    nwk_company nc 

                            WHERE
                                    ni.NAICS = ncio.company_id
                            ORDER BY 

                                    NAICS

Answer 1

如果连接条件正确，这应该适合您（ni.NAICS = ncio.company_id）

<?php
session_start();

$singer_name = ($_POST['singer_name']);
$song_name = ($_POST['song_name']);
$ctg_name = ($_POST['ctg_name']);
$mp3 = ($_POST['mp3']);
$album_cover = ($_POST['album_cover']);
$link = mysqli_connect("example.com", "user", "pass", "example");
$sql = "INSERT INTO song (singer_name, song_name, ctg_name, mp3, album_cover) 
VALUES ('$insertsinger_name, $insertsong_name, $insertctg_name, $insertmp3, $insertalbum_cover')";  
    if(mysqli_query($link, $sql)){
            mysqli_close($link);
                    session_write_close();
                    header("location: songadmin.php");
                    exit();
        } else{
            die("Query Failed");
        }

  ?>

MySQL查询子串长度检查并将相应的子串总和为1

1 个答案: