简单的mysql按天，按周，按月，按季度，按年统计数据

mysql是常用的数据库，php+mysql是常用的组合，在web开发后台总有一些需要统计的图表、数据。下面是常用的mysql按日、周、月、季查询的方式。条件自己定义。
说明：
create_time：是需要查询的时间字段
createTime：是查询的别名
tableName：是需要查询的表名
id、payPrice、refundMoney：仅代表某些字段。
SQL语句如下：

/*查询2小时前的数据*/
SELECT *
FROM tableName
WHERE  create_time < DATE_SUB(NOW(), INTERVAL 2 HOUR)
ORDER BY create_time DESC;

/*按天统计*/
SELECT
    count(id) countNum,
    DATE(create_time) createTime
FROM
    tableName
GROUP BY
    DATE(create_time)
ORDER BY
    DATE(create_time) DESC;


/*按周统计*/
SELECT
    count(id) countNum,
    WEEK(create_time) createTime
FROM
    tableName
GROUP BY
    WEEK(create_time)
ORDER BY
    WEEK(create_time) DESC;


/*按月统计*/
SELECT
    count(id) countNum,
    MONTH(create_time) createTime
FROM
    tableName
GROUP BY
    MONTH(create_time)
ORDER BY
    MONTH(create_time) DESC;


/*按季度统计*/
SELECT
    count(id) countNum,
    QUARTER(create_time) createTime
FROM
    tableName
GROUP BY
    QUARTER(create_time)
ORDER BY
    QUARTER(create_time) DESC;

/*按年统计*/
SELECT
    count(id) countNum,
    YEAR(create_time) createTime
FROM
    tableName
GROUP BY
    YEAR(create_time)
ORDER BY
    YEAR(create_time) DESC;