Question

我曾尝试构建一个mysql存储过程，但似乎有不同的错误，我只是试图从存储过程中运行一个预准备语句，以实现动态地在表中插入一些数据。

任何人都可以检查并告诉我错误在哪里吗？

由于

    DELIMITER $$
    CREATE PROCEDURE insert_tracking(IN deviceid VARCHAR(15),IN timing timestamp,IN valid tinyint(1),IN latitude double,IN longitude double,IN speed double,IN course double,IN power double,IN comando varchar(45))
    BEGIN
        DECLARE query VARCHAR(150);
        SET query = "INSERT INTO tracking_? (device_id,time,valid,latitude,longitude,speed,course,power,command) VALUES (?,?,?,?,?,?,?,?,?)";
        PREPARE stmt FROM query;
        EXECUTE stmt USING deviceid,deviceid,timing,valid,latitude,longitude,speed,course,power,comando;
    END $$

我也尝试了这种连接，但它不起作用。

    DELIMITER $$
    CREATE PROCEDURE insert_tracking(IN deviceid VARCHAR(15),IN timing timestamp,IN valid tinyint(1),IN latitude double,IN longitude double,IN speed double,IN course double,IN power double,IN comando varchar(45))
    BEGIN
        DECLARE query VARCHAR(200);
        SET query = CONCAT('INSERT INTO tracking_',deviceid,' (device_id,time,valid,latitude,longitude,speed,course,power,command) VALUES (?,?,?,?,?,?,?,?,?)');
        PREPARE stmt FROM query;
        EXECUTE stmt USING deviceid,timing,valid,latitude,longitude,speed,course,power,comando;
        DEALLOCATE PREPARE stmt;
    END $$

编辑后我有了这个，我测试了concat语句并且它们分开工作但是准备好的语句一直存在问题，它不起作用。

    DELIMITER $$
    CREATE PROCEDURE insert_tracking(IN deviceid VARCHAR(15),IN timing timestamp,IN valid tinyint(1),IN latitude double,IN longitude double,IN speed double,IN course double,IN power double,IN comando varchar(45))
    BEGIN
        SET @deviceid = deviceid;
        SET @nsert = CONCAT('INSERT INTO tracking_',@deviceid); 
        SET @query = CONCAT(@nsert,' (device_id,time,valid,latitude,longitude,speed,course,power,command) VALUES ("?","?","?","?","?","?","?","?","?")');
        SET @fquery = @query;
        PREPARE stmt FROM @fquery;
        EXECUTE stmt USING deviceid,timing,valid,latitude,longitude,speed,course,power,comando;
    END $$

Answer 1

我认为这是因为表和列名称不能被预准备语句中的参数替换。尝试获取完整的表名并测试是否要验证。

代码取自（http://dev.af83.com/2007/05/30/use-parameters-for-field-and-table-names-in-a-mysql-prepare-statement-to-create-truly-dynamic-sql.html）学分

此函数可以允许动态表名和列名

DELIMITER //
DROP FUNCTION  IF EXISTS substrCount//
CREATE FUNCTION substrCount(x varchar(255), delim varchar(12)) returns int
return (length(x)-length(REPLACE(x, delim, '')))/length(delim);//

DROP FUNCTION  IF EXISTS charsplit//
CREATE FUNCTION charsplit(x varchar(255), delim varchar(12), pos int) returns varchar(255)
return replace(substring(substring_index(x, delim, pos), length(substring_index(x, delim, pos - 1)) + 1), delim, '');//

DROP FUNCTION  IF EXISTS replacefirst//
CREATE FUNCTION replacefirst(haystack varchar(255), needle varchar(255),replacestr varchar(255)) returns varchar(255)
BEGIN
    IF LOCATE(needle,haystack)>0 THEN
        SET @replaced=concat(left(haystack,LOCATE(needle,haystack)-LENGTH(needle)),replacestr,right(haystack,LENGTH(haystack)-LOCATE(needle,haystack)));
    ELSE
        SET @replaced=haystack;
    END IF;
    RETURN @replaced;
END;//

DROP FUNCTION  IF EXISTS properprepare//
CREATE FUNCTION properprepare(template varchar(255), args varchar(255)) returns varchar(255)
BEGIN
 SET @i=0;
 SET @numargs = substrCount(args,',');
  WHILE @i <= @numargs DO
      SET @i= @i+ 1;
      SET template=replacefirst(template,'?',charsplit(args,',',@i));
  END WHILE;
RETURN template;
END;//

DELIMITER ;

在mysq存储过程中准备好语句

1 个答案: