### The error may involve defaultParameterMap ### The error occurred while setting parameters

Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Query was empty
; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Query was empty]

 

今天用mybatis+pageHelp時發生這個錯誤，原因是：

錯誤代碼：

    public PageInfo<Log> getLogPage(Integer pageNum) {
        //設置每頁顯示數量
        int pageSize = 5;
        PageHelper.startPage(pageNum, pageSize);
        //執行分頁查詢
        NMRoutingToken token = new NMRoutingToken("LOG_DATA_SOURCE_KEY");
        List<String> tableNameList = logMapper.selectAlltableName();
        
        NMRoutingToken token1 = new NMRoutingToken("LOG_DATA_SOURCE_KEY");
    
        List<Log> logList=logMapper.selectAllLog(tableNameList);
        //對獲取的數據進行包裝
        int navigatePages = 6;
        PageInfo<Log> page = new PageInfo<>(logList, navigatePages);
        return page;
    }    

正確：

    public PageInfo<Log> getLogPage(Integer pageNum) {

        //執行分頁查詢
        NMRoutingToken token = new NMRoutingToken("LOG_DATA_SOURCE_KEY");
        List<String> tableNameList = logMapper.selectAlltableName();
        
        NMRoutingToken token1 = new NMRoutingToken("LOG_DATA_SOURCE_KEY");
        //設置每頁顯示數量
        int pageSize = 5;
        PageHelper.startPage(pageNum, pageSize);
        List<Log> logList=logMapper.selectAllLog(tableNameList);
        //對獲取的數據進行包裝
        int navigatePages = 6;
        PageInfo<Log> page = new PageInfo<>(logList, navigatePages);
        return page;
    }

pageHelp的頁面設置應該在指定的sql前