格式化日期字段為年月日格式：

DATE_FORMAT(create_time, '%Y%m%d')

通過日期查詢對(duì)應(yīng)的日期的總數(shù)：

SELECT
DATE_FORMAT(create_time, '%Y%m%d') date,
count(*) count
FROM
system
GROUP BY
DATE_FORMAT(create_time, '%Y%m%d');

count 的條件查詢

查詢type字段為SOURCE_SEARCH 的count
count(type= 'SOURCE_SEARCH' OR NULL)
count(type= 'TYPE' and type2 = 'TYPE2' OR NULL)

通過日期分組查詢條件下的count

SELECT
DATE_FORMAT(create_time, '%Y%m%d') date,
count(type= 'TYPE' OR NULL) count
FROM
system
GROUP BY
DATE_FORMAT(create_time, '%Y%m%d');

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