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题解 | #月总刷题数和日均刷题数#

```WITH t AS ( SELECT a.uid, a.score, b.exam_id, IF ( ( a.score - MIN( score ) over ( PARTITION BY exam_id ) ) / ( MAX( score ) over ( PA...

Mysql

2022-02-28

0 351

题解 | #月总刷题数和日均刷题数#

```WITH t AS ( SELECT uid, nick_name, CHAR_LENGTH( nick_name ) len FROM user_info ) SELECT uid, IF ( len > 13, CONCAT( LEFT ( nick_name, 10 ), '.....

Mysql

2022-02-25

1 303

题解 | #月总刷题数和日均刷题数#

```SELECT exam_id, SUBSTRING_INDEX( tag, ',', 1 ) tag, SUBSTRING_INDEX( SUBSTRING_INDEX( tag, ',', 2 ), ',',- 1 ) difficulty, SUBSTRING_INDEX( tag...

Mysql

2022-02-25

0 320

题解 | #月总刷题数和日均刷题数#

```WITH t AS ( SELECT *, DAY ( LAST_DAY( submit_time ) ) days, DATE_FORMAT( submit_time, "%Y%m" ) submit_month FROM practice_record WHERE...

Mysql

2022-02-25

0 218

题解 | #商品交易(网易校招笔试真题)#

```SELECT age, count( device_id ) number FROM ( SELECT *, SUBSTRING_INDEX( SUBSTRING_INDEX( PROFILE, ',', 3 ), ',',- 1 ) age FROM user_submit ) t ...

Mysql

2022-02-25

0 213

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT *, SUBSTRING_INDEX( PROFILE, ',',- 1 ) gender FROM user_submit ) SELECT gender, count( gender ) number FROM t GROUP BY gende...

Mysql

2022-02-24

0 292

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT a.device_id, a.university, a.answer_cnt, b.question_id FROM user_profile a LEFT JOIN question_practice_detail b O...

Mysql

2022-02-24

0 225

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT a.device_id, a.university, a.answer_cnt, b.question_id FROM user_profile a LEFT JOIN question_practice_detail b O...

Mysql

2022-02-24

0 227

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT *, CASE WHEN age > 24 THEN "25岁及以上" WHEN 20 <= age <= 24 THEN "20-24岁" ELSE "其他" END age_cnt FROM user_profile ) SELECT...

Mysql

2022-02-24

0 213

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT a.device_id, b.question_id, b.result, b.date FROM user_profile a LEFT JOIN question_practice_detail b ON a.device...

Mysql

2022-02-22

0 237