Question

我正在尝试创建一个搜索函数，在GridView中搜索某个值然后返回该行。我在MySQL工作台中测试了这个查询并且它可以工作但是当在visual studio中运行查询时我得到了这个错误：

您的SQL语法有错误;检查手册对应于您的MySQL服务器版本，以便使用正确的语法靠近＆＃39;？parameter0＆＃39;在第23行

      StringBuilder SQL = new StringBuilder(SearchSQL);
                if (SearchFieldKey != null && SearchFieldKey.Length > 0)
                {
                    if (SearchTerms != null)
                    {
                        SQL.Append(" HAVING ");
                        for (int i = 0; i < SearchFieldKey.Length; i++)
                        {
                            if (SearchFields.ContainsKey(SearchFieldKey[i]))
                            {

                                SQL.Append(SearchFields[SearchFieldKey[i]] + " LIKE ?parameter" + i.ToString());
                                param.Add(new MySqlParameter("parameter" + i.ToString(), "%" + SearchTerms[i] + "%"));

                                if (i != SearchFieldKey.Length - 1)
                                    SQL.Append(" OR ");
                            }
                            else
                                throw new Exception("Error: Attempted to search on invalid field. Check SearchFields Argument.");
                        }
                    }
                }

 SQL.Append(" '); ");
 SQL.Append ("prepare stmt from @sql; execute stmt; deallocate prepare stmt;");

调试时，我复制了正在运行的确切查询并将其粘贴到Workbench中，它可以正常运行。所以我不知道为什么它不会在视觉工作室中运行。

查询从此代码运行：

 DataTable dtJobs = Job.CustomFill(SQL.ToString(), param);

传入的参数是＆＃34;％TESTING％＆＃34;

显示数据库中行的查询：

private static string SearchSQL
    {
        get
        {
            return @" 
                                                            SET group_concat_max_len=10000000;
                                                            set @sql = null;
                                                                select
                                                                  group_concat(distinct
                                                                    concat(
                                                                       'MAX(CASE WHEN pt.Code = ''', 
                                                                        pt.Code ,
                                                                        ''' THEN jp.AdvisedQty ELSE 0 END) AS `',
                                                                        pt.Code, '`'
                                                                    )
                                                                  ) into @sql
                                                                 FROM customer c
                                                        LEFT JOIN job_address ja ON c.AccountCode = ja.Code AND c.Company_ID = ja.Company_ID
                                                        JOIN  AddressType jat ON ja.AddressType = jat.ID and jat.Description = 'Debtor'
                                                        LEFT JOIN job_new jn ON ja.JobID = jn.ID
                                                        LEFT JOIN job_pieces jp ON ja.JobID = jp.ID
                                                        LEFT JOIN piecestype pt on jp.TypeID = pt.ID
                                                    WHERE c.Company_ID = ?compid;

                                        set @sql = concat('select 
                                                            c.Name,
                                                            COUNT(distinct jn.ID) as Jobs,
                                                            (SELECT Name FROM job_address WHERE AddressType =3 AND JobID = jn.ID) as CollectName,
                                                            (SELECT Name FROM job_address WHERE AddressType =2 AND JobID = jn.ID) as DeliverName,
                                                            ', @sql, ' 
                                                        FROM customer c
                                                        LEFT JOIN job_address ja ON c.AccountCode = ja.Code AND c.Company_ID = ja.Company_ID
                                                        JOIN  AddressType jat ON ja.AddressType = jat.ID and jat.Description = ''Debtor''
                                                        LEFT JOIN job_new jn ON ja.JobID = jn.ID
                                                        LEFT JOIN job_pieces jp ON ja.JobID = jp.ID
                                                        LEFT JOIN piecestype pt on jp.TypeID = pt.ID
                                                   WHERE c.Company_ID = ', ?compid,
                                                    ' GROUP BY c.ID


                                                                            ";
        }
    }

因此，我的搜索查询将HAVING c.Name LIKE "%PRL%" ');放在查询的GROUP BY之后。然后Append语句将准备好的stmts放在查询的末尾。

Answer 1

根据您发布的SQL，问题是双引号：

HAVING c.Name LIKE "%PRL%"

SQL标准说双引号用于标识符名称，如别名，列，表，模式，过程，视图或数据库。如果你想要字符串文字，你需要在这里使用单引号：

HAVING c.Name LIKE '%PRL%'

这是MySql在遵循标准方面做得不好的很多地方之一（取决于你如何设置ANSI_QUOTES），但如果你想确定，请尝试使用单引号。

搜索SQL查询中的错误

1 个答案: