msql获取本年每个月新增的数据没有显示0

如果您想要获取本年每个月新增的数据并且要显示0，可以使用 MySQL 的 IFNULL 函数以及 LEFT JOIN 操作，示例代码如下：

SELECT 
    MONTH(date_col) AS month, 
    IFNULL(COUNT(*), 0) AS count 
FROM 
    your_table 
RIGHT JOIN 
    (
        SELECT 1 AS month 
        UNION SELECT 2 AS month 
        UNION SELECT 3 AS month 
        UNION SELECT 4 AS month 
        UNION SELECT 5 AS month 
        UNION SELECT 6 AS month 
        UNION SELECT 7 AS month 
        UNION SELECT 8 AS month 
        UNION SELECT 9 AS month 
        UNION SELECT 10 AS month 
        UNION SELECT 11 AS month 
        UNION SELECT 12 AS month 
    ) AS months ON MONTH(date_col) = months.month 
WHERE 
    YEAR(date_col) = YEAR(CURRENT_DATE()) 
GROUP BY 
    months.month;

这段 SQL 查询语句会返回当前年份中每个月份的新增数据量，如果某个月份没有新增数据，则对应的 count 字段会显示为0。