最近作統計用到的幾個經常使用sql

計算同比

SELECT
	old.now_time,
	ROUND( ( new.count - old.count ) / old.count * 100, 2 ),
	new.count ncount,
	old.count ocount 
FROM (
SELECT
	sum( IF ( b.count > 1, 1, 1 ) ) count,
	b.now_time,
	b.tenant_code 
FROM
	(
	SELECT
		date_format( ro.create_dt, '%Y-%m' ) AS now_time,
		a.tenant_code,
		a.order_no,
		count( a.id ) count 
	FROM
		t_rep_order_timeout a 
	INNER JOIN t_rep_order ro on 
		a.tenant_code = ro.tenant_code and a.order_no = ro.order_no
	WHERE
		a.tenant_code = 'zlyy' 
	GROUP BY
		date_format( ro.create_dt, '%Y-%m' ),
		a.tenant_code,
		a.order_no 
	) b 
GROUP BY
	b.now_time,
	b.tenant_code
	) new 
LEFT JOIN
(SELECT
	sum( IF ( b.count > 1, 1, 1 ) ) count,
	b.now_time,
	b.tenant_code 
FROM
	(
	SELECT
		date_format( DATE_ADD( ro.create_dt, INTERVAL 1 YEAR ), '%Y-%m') AS now_time,
		a.tenant_code,
		a.order_no,
		count( a.id ) count 
	FROM
		t_rep_order_timeout a 
	INNER JOIN t_rep_order ro on 
		a.tenant_code = ro.tenant_code and a.order_no = ro.order_no
	WHERE
		a.tenant_code = 'zlyy' 
	GROUP BY
		date_format( DATE_ADD( ro.create_dt, INTERVAL 1 YEAR ), '%Y-%m'),
		a.tenant_code,
		a.order_no 
	) b 
GROUP BY
	b.now_time,
	b.tenant_code) old 
	on old.tenant_code = new.tenant_code and old.now_time = new.now_time

計算環比

SELECT
	old.now_time,
	ROUND( ( new.count - old.count ) / old.count * 100, 2 ),
	new.count ncount,
	old.count ocount 
FROM (
SELECT
	sum( IF ( b.count > 1, 1, 1 ) ) count,
	b.now_time,
	b.tenant_code 
FROM
	(
	SELECT
		date_format( ro.create_dt, '%Y-%m' ) AS now_time,
		a.tenant_code,
		a.order_no,
		count( a.id ) count 
	FROM
		t_rep_order_timeout a 
	INNER JOIN t_rep_order ro on 
		a.tenant_code = ro.tenant_code and a.order_no = ro.order_no
	WHERE
		a.tenant_code = 'zlyy' 
	GROUP BY
		date_format( ro.create_dt, '%Y-%m' ),
		a.tenant_code,
		a.order_no 
	) b 
GROUP BY
	b.now_time,
	b.tenant_code
	) new 
LEFT JOIN
(SELECT
	sum( IF ( b.count > 1, 1, 1 ) ) count,
	b.now_time,
	b.tenant_code 
FROM
	(
	SELECT
		date_format( DATE_ADD( ro.create_dt, INTERVAL 1 MONTH ), '%Y-%m') AS now_time,
		a.tenant_code,
		a.order_no,
		count( a.id ) count 
	FROM
		t_rep_order_timeout a 
	INNER JOIN t_rep_order ro on 
		a.tenant_code = ro.tenant_code and a.order_no = ro.order_no
	WHERE
		a.tenant_code = 'zlyy' 
	GROUP BY
		date_format( DATE_ADD( ro.create_dt, INTERVAL 1 MONTH ), '%Y-%m'),
		a.tenant_code,
		a.order_no 
	) b 
GROUP BY
	b.now_time,
	b.tenant_code) old 
	on old.tenant_code = new.tenant_code and old.now_time = new.now_time

獲取某一年份全部月份

SELECT
CASE
		
	WHEN
		length( mon ) = 1 THEN
			concat( '2019-0', mon ) ELSE concat( '2019-', mon ) 
		END months 
FROM
	( SELECT @m := @m + 1 mon FROM t_rep_order_timeout, ( SELECT @m := 0 ) a ) aa 
	LIMIT 12

此處所用的輔助表t_rep_oder_timeot表數據必須超過12條

刪除表內的重複數據

DELETE t 
FROM
	interview t
	LEFT JOIN ( SELECT title, min( id ) AS min_id FROM interview GROUP BY title ) t1 ON t.id = t1.min_id 
WHERE
	t1.min_id IS NULL;

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