Enumerate rows in mysql based on groups with dates in different columns - mysql

I have a question very similar to this one, but different (aka, I couldn't extend the answer to that one to fit my purposes. Due to the second WHERE condition, specifically).
I have a table which tracks the visit number for customers. There are two types of visits:
| ID | InStoreVisit | InStoreDate | OnlineVisit | OnlineDate |
|----|--------------|-------------|-------------|------------|
| 1 | 1 | 1/1/11 | | |
| 1 | 2 | 1/2/11 | | |
| 1 | | | 1 | 1/3/11 |
| 1 | 3 | 1/4/11 | | |
| 2 | | | 1 | 2/2/12 |
| 2 | 1 | 2/3/12 | | |
| 2 | | | 2 | 2/4/12 |
I need to create a new column which has a sort of 'global visit number' as such:
| ID | InStoreVisit | InStoreDate | OnlineVisit | OnlineDate | GobalVisit |
|----|--------------|-------------|-------------|------------|------------|
| 1 | 1 | 1/1/11 | | | 1 |
| 1 | 2 | 1/2/11 | | | 2 |
| 1 | | | 1 | 1/3/11 | 3 |
| 1 | 3 | 1/4/11 | | | 4 |
| 2 | | | 1 | 2/2/12 | 1 |
| 2 | 1 | 2/3/12 | | | 2 |
| 2 | | | 2 | 2/4/12 | 3 |
I'm getting mixed up on the WHERE condition with which I can do the self-join. Any advice greatly appreciated.

Related

how to sort sql data for given table?

+---------+----------------+--------+
| aid | fn | col_no |
+---------+----------------+--------+
| 2011768 | ABDUL | 5 |
| 2011499 | ABDULLA | 4 |
| 2011198 | ADNAN | 3 |
| 2011590 | AKSHAYA PRAISY | 2 |
| 2011749 | AMIR | 1 |
| 2011213 | AMOGHA | 5 |
| 2011027 | ANU | 4 |
| 2011046 | ANUDEV D | 3 |
| 2011435 | B S SAHANA | 2 |
| 2011112 | BENAKA | 1 |
+---------+----------------+--------+
How to sort the number like col_no as 1 2 3 4 5 and again repeat as 1 2 3 4 5?
i need output like this
+---------+----------------+--------+
| aid | fn | col_no |
+---------+----------------+--------+
| 2011749 | AMIR | 1 |
| 2011590 | AKSHAYA PRAISY | 2 |
| 2011198 | ADNAN | 3 |
| 2011499 | ABDULLA | 4 |
| 2011768 | ABDUL | 5 |
| 2011112 | BENAKA | 1 |
| 2011435 | B S SAHANA | 2 |
| 2011046 | ANUDEV D | 3 |
| 2011027 | ANU | 4 |
| 2011213 | AMOGHA | 5 |
+---------+----------------+--------+
You can use row_number() partition by col_no:
select t.*
from t
order by row_number() over (partition by col_no order by fn),
col_no;
Here is a db<>fiddle.

MySQL Events in information system into programming language

For example I have 3 tables:
Users:
+----+-------------+
| id | nickname |
+----+-------------+
| 1 | Don2Quixote |
| 2 | Pechenye |
| 3 | Maryana |
| 4 | Luman |
| 5 | Tester |
+----+-------------+
Matches:
+----+----------+---------------------+
| id | owner_id | match_end_timestamp |
+----+----------+---------------------+
| 1 | 1 | 1610698498 |
| 2 | 2 | 1610699911 |
| 3 | 3 | 1610701672 |
| 4 | 1 | 1610711211 |
| 5 | 1 | 1610725289 |
+----+----------+---------------------+
matches_players:
+----------+------+-------------+---------+
| match_id | team | slot_number | user_id |
+----------+------+-------------+---------+
| 1 | 1 | 1 | 1 |
| 2 | 1 | 2 | 2 |
...........................................
| 3 | 1 | 1 | 3 |
+----------+------+-------------+---------+
match_end_timestamp is future timestamp. My goal is to get event in programming language on reaching this date and send notification to each player in table matches_players where match_id is id of just ended match. Is it possible? Or the only solution is to store additional timer in my programming language in RAM?

Complex pivoting in mysql

I have a table in MySQL that has data and I want to achieve some sort of pivoting from the table, which has become complicated for me. I have tried looking into this but nothing seems to work for me. This is the structure of my table :
roomid| day| 1 | 2 | 3 | 4 | 5 | 6 |
------+----+---+---+---+---+---+---+
1 | 1 |BIO| | | | | |
1 | 2 | |CHE| | | | |
1 | 3 | | | | | |ENG|
1 | 4 | | |KIS| | | |
1 | 5 | | | | | |PHY|
2 | 1 |BIO| | | | | |
2 | 2 | |CHE| | | | |
2 | 3 | | | | |ENG| |
2 | 4 | | |KIS| | | |
2 | 5 | | | | | |PHY|
This table is holding timetable data, the roomid is id for rooms and the day is days from monday to friday (1 to 5). The columns 1 to 6 are period ids.
I need to organize the data to achieve results that show period ids for each class, each day. something like this :
|roomid| 1 | 2 | 3 | 4 | 5 | 6 | 1 | 2 | 3 | 4 | 5 | 6 | 1 | 2 | 3 | 4 | 5 | 6 | 1 | 2 | 3 | 4 | 5 | 6 | 1 | 2 | 3 | 4 | 5 | 6 |
-------+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
1 |BIO| | | | | | |CHE| | | | | | | | | |ENG| | |KIS| | | | | | | | |PHY|
2 |BIO| | | | | | |CHE| | | | | | | | | |ENG| | |KIS| | | | | | | | |PHY|
Kindly notice that the period ids repeat themselves for different days.
You can use conditional aggreagtion:
select room_id,
max(case when day = 1 then slot_1 end) as day_1_slot_1,
max(case when day = 1 then slot_2 end) as day_1_slot_2,
. . .
max(case when day = 2 then slot_1 end) as day_2_slot_1,
max(case when day = 2 then slot_2 end) as day_2_slot_2,
. . .
from schedule s
group by room_id
While not claiming to be a definitive solution, a normalised design might be somewhat as follows. Frankly, it stretches credulity to suggest that the present design is somehow more appropriate than this.
+--------+-----+------+---------+
| roomid | day | slot | subject |
+--------+-----+------+---------+
| 1 | 1 | 1 | BIO |
| 2 | 1 | 2 | BIO |
| 1 | 2 | 2 | CHE |
| 2 | 2 | 2 | CHE |
| 1 | 4 | 3 | KIS |
| 2 | 4 | 3 | KIS |
| 2 | 3 | 5 | ENG |
| 1 | 3 | 6 | ENG |
| 1 | 5 | 6 | PHY |
| 2 | 5 | 6 | PHY |
+--------+-----+------+---------+

Join two tables on nearest matching string

I have a query_table Table and wants to join with match_table Table with nearest matching string. If it was vice-versa then 'like' would have worked but have no idea how to do this.
query_table
+----+------------------+
| id | string |
+----+------------------+
| 1 | fcc9e8796feb |
| 2 | fcdbd7ebcf89 |
| 3 | fccc87896feb |
| 4 | fcc7c7896fef |
| 5 | fcced777aaaf |
+----+------------------+
match_table
+----+-----------+
| id | match_code|
+----+-----------+
| 1 | fcff |
| 2 | fcccc |
| 3 | fccc8 |
| 4 | fccc9 |
| 5 | fccdb |
| 6 | fccdc |
| 7 | fccd8 |
| 8 | fcce |
| 9 | fcced |
| 10 | fccee |
| 11 | fcce6 |
| 12 | fcc7b |
| 13 | fcc7c |
| 14 | fcc8e |
| 15 | fcc87 |
| 16 | fcc88 |
| 17 | fcc9e |
| 18 | fcdbb |
| 19 | fcdbc |
| 20 | fcdbd |
+----+-----------+
I expect
result
+----+------------------+----+----------------+
| id | string | id | match_code |
+----+------------------+----+----------------
| 1 | fcc9e8796feb | 17 | fcc9e |
| 2 | fcdbd7ebcf89 | 20 | fcdbd |
| 3 | fccc87896feb | 3 | fccc8 |
| 4 | fcc7c7896fef | 13 | fcc7c |
| 5 | fcced777aaaf | 9 | fcced |
+----+------------------+----+----------------+

Selected Child Categories based on parent categories from another table

I have two tables
rules
With three step hierarchy
|id | name | parent |
|---|-------|--------|
| 1 | A | 0 |
| 2 | B | 0 |
| 3 | A(1) | 1 |
| 4 | A(2) | 1 |
| 5 | B(1) | 2 |
| 6 | A(1.1)| 3 |
| 7 | A(1.2)| 3 |
| 8 | A(2.1)| 4 |
| 9 | B(1.1)| 5 |
| 10| A(3) | 1 |
Subject
|id | date | rules | group |
|---|---------------------|-------|-------|
| 1 | 2016-05-20 18:24:20 | 2 | AQR48 |
| 2 | 2016-05-20 19:31:17 | 5 | AQR52 |
| 3 | 2016-05-21 18:11:37 | 6,7,4 | AQR48 |
I need to get second step rules based on group and ruleid(first step) of subject table data
When group = 'AQR48' and rules.parent=1 result should be
|id | name | parent |
|---|-------|--------|
| 3 | A(1) | 1 |
| 4 | A(2) | 1 |
I tried it like this but with out success.
select rules.id,rules.name,rules.parent from rules left join subject on find_in_set(rules.id,subject.rules) where rules.parent=1 AND subject.group='AQR48'
With this I get output as
|id | name | parent |
|---|-------|--------|
| 4 | A(2) | 1 |
Anyone could help me with this