SQLSTR是别名，在MySQL5.7以上版本能通过，在5.0上提示unknow column ‘SQLSTR’错误，我不知道应该怎么修改（因为客户关系不能通过mysql版本）,请各位大神指点！

BEGIN DECLARE sTYPE VARCHAR(20); DROP TEMPORARY TABLE IF EXISTS temp_public_data; CREATE TEMPORARY TABLE temp_public_data SELECT DATE_FORMAT(FROM_UNIXTIME(n.inputtime),'%Y-%m-%d') as days, DATE_FORMAT(FROM_UNIXTIME(n.inputtime),'%Y-%m') as months, DATE_FORMAT(FROM_UNIXTIME(n.inputtime),'%Y') as years, DATE_FORMAT(FROM_UNIXTIME(n.inputtime),'%u') as weeks, count(n.id) as pubnum,n.username from v9_news as n WHERE DATE_FORMAT(FROM_UNIXTIME(n.inputtime),'%Y-%m-%d') BETWEEN pDayBegin AND pDayEnd GROUP BY days,n.username; IF pType=1 THEN SET sType = "years"; ELSEIF pType=2 THEN SET sType = "months"; ELSEIF pType=3 THEN SET sType = "weeks"; ELSEIF pType=5 THEN SET sType = "days"; END IF; SET @EE = ""; SELECT @EE:= CONCAT(@EE,',SUM(IF(username=\'',username,'\',pubnum,0)) AS \'',username,'\'') AS **SQLSTR** FROM (SELECT DISTINCT username FROM temp_public_data) A ORDER BY **LENGTH(SQLSTR)** DESC LIMIT 0,1; SET @SQL = CONCAT('SELECT IFNULL(',sType,',\'TOTAL\') AS MONTH'); SET @SQL = CONCAT(@SQL,@EE); SET @SQL = CONCAT(@SQL,',SUM(pubnum) as TOTAl '); SET @SQL = CONCAT(@SQL,' FROM temp_public_data'); SET @SQL = CONCAT(@SQL,' GROUP BY ',sType,' WITH ROLLUP;'); #SELECT @SQL; PREPARE stmt FROM @SQL; EXECUTE stmt; DROP TEMPORARY TABLE IF EXISTS temp_public_data; END