Update with results of Ordered Select into Column - mysql

I have a simple table with four columns: id | name | score | rank that looks like this:
id | name | score | rank
---|------|-------|-----
1 | Bob | 99 | -
2 | Jim | 88 | -
3 | Rex | 103 | -
4 | Zus | 55 | -
I'd like to sort these rows by score (descending) and store the approriate ranking in the rank column for each row.
Currently, I'm using the following code to create an alias column that has the rankings:
SET #rank:=0;
SELECT *, #rank:=#rank+1 AS rank_test FROM test ORDER BY score DESC
Which returns:
id | name | score | rank | rank_test
---|------|-------|------|----------
3 | Rex | 103 | - | 1
1 | Bob | 99 | - | 2
2 | Jim | 88 | - | 3
4 | Zus | 55 | - | 4
How can I transfer the result of the rank_test alias into the rank column?
I've researched a lot of answers but can't seem to get anything to work. Fairly new to SQL so I apologize if it's a simple solution. Thank you!

Related

How to select the most spanning ranges

My table looks like
+----+------+----+
| Id | from | to |
+----+------+----+
| 1 | 1 | 10 |
| 1 | 10 | 12 |
| 1 | 12 | 23 |
| 1 | 24 | 26 |
| 2 | 2 | 8 |
| 2 | 3 | 4 |
| 2 | 4 | 10 |
+----+------+----+
Now I want to group by Id and select the most spanning range.
So the result table should look like this:
+----+-------------+
| Id | range |
+----+-------------+
| 1 | 1-23, 24-26 |
| 2 | 2-10 |
+----+-------------+
I do not even know how to start.
Thanks in advance for the help!
You can achieve something similar to this by writing a MySQL select query with the CONCAT() function. You can use GROUP BY to categorize the data. But keep in mind that from,to and range are reserved words in MySQL. Therefore, I'll use fooFrom, fooRange and fooTo as column name for this example
Example:
SELECT Id, CONCAT(fooFrom, "-", fooTo) AS "fooRange" FROM fooTable GROUP BY id;
This example code will output:
id | fooRange
1 | 5-6
2 | 12-88
But I'm not sure about how to concat all the content into a one-column value.

Join 2 tables and sum with condition in codeigniter

I have 2 tables
Table1: customers:
-------------
| id | name |
-------------
| 1 | Mark |
-------------
| 2 | Tom |
-------------
| 3 | John |
Table2: sales:
-----------------------------------
|sid | customerid | price | state |
-----------------------------------
| 10 | 1 | 12000 | 0 |
-----------------------------------
| 11 | 2 | 13500 | 1 |
-----------------------------------
| 12 | 2 | 23000 | 1 |
-----------------------------------
| 13 | 3 | 26000 | 0 |
-----------------------------------
| 14 | 1 | 66000 | 1 |
-----------------------------------
the state column is 0=no dep and 1=dept
I want to list the customers that have DEPT by checking them in the sales table. Now i'm looping the customers and checking them one by one. and it works! but when the number of rows in the customer table grows the page slows down. i want to make this by an SQL query. can anyone help me please ?
the result will be like this:
Mark 66000
Tom 36500
By the Following query, you will get the same output as you want. The joining of tables will be executed on the filtered data using where condition
$this->db->select('customers.name,sum(sales.price)')
->from('customers')
->join('sales','sales.customerid = customers.id','left')
->where('sales.state !=0')
->group_by('customers.name');
->get()->result_array();
You can simply group by customer id in sales table. Code will be like this
return $this->db->select('MAX(customers.name) AS name, SUM(sales.price) as price')->join('sales', 'sales.customerid = customers.id')->where('sales.state', 1)->group_by('customers.id')->get('customers')->result();

How can I go through all ids and sum all copies of IDs scores together to one ID?

I'm trying to do something like a sports scoreboard for a school project but I ran into problem where I'm trying to add the game score to one big leaderboard but I have a problem. Since I wanna make it fully automatic.
I wanna make it loop through all IDs and count them all to their own ID.
From this
+-----+-------+--+
| ID | Score | |
+-----+-------+--+
| 1 | 25 | |
| 2 | 10 | |
| 3 | 21 | |
| 1 | 25 | |
| 2 | 10 | |
| 3 | 21 | |
+-----+-------+--+
To this
+-----+-------+--+
| ID | Score | |
+-----+-------+--+
| 1 | 50 | |
| 2 | 20 | |
| 3 | 43 | |
+-----+-------+--+
I've tried some I loops but havent gotten any of them working! And also tried to use Where ID = ID but it just counts all together
SELECT SUM(`Score`) FROM `Scores` WHERE `ID` = '1";
It sounds like you want to group by ID, and then sum within the group:
SELECT ID, SUM(Score) AS Score FROM Scores GROUP BY ID

MySQL Group By - Top 3 rows and nth row

I have a MySQL table like this:
+------+--------+--------+
| ID | UserID | Score |
+------+--------+--------+
| 1 | 3 | 12 |
| 2 | 3 | 11 |
| 3 | 3 | 12 |
| 4 | 2 | 14 |
| 5 | 4 | 8 |
| 6 | 2 | 13 |
+------+--------+--------+
From this I want to top 3 scores from entire table and a top score from particular user
+------+--------+--------+
| ID | UserID | Score |
+------+--------+--------+
| 4 | 2 | 14 |
| 6 | 2 | 13 |
| 3 | 3 | 12 |
| 5 | 4 | 8 |
+------+--------+--------+
Is this something I can get done in a single query?
Any help is appreciated
Thanks in advance!
spoiler alert ;)
(SELECT * FROM tableA ORDER BY score DESC LIMIT 3)
UNION
(SELECT * FROM tableB WHERE UserID = 4 ORDER BY score DESC LIMIT 1);
For certain definitions of "single query", sure... If you're willing to use sub queries or a union.
The best performance will probably come from two queries, but you can join them in a UNION for convenience if you wish.

Remove duplicates SQL while ignoring key and selecting max of specified column

I have the following sample data:
| key_id | name | name_id | data_id |
+--------+-------+---------+---------+
| 1 | jim | 23 | 098 |
| 2 | joe | 24 | 098 |
| 3 | john | 25 | 098 |
| 4 | jack | 26 | 098 |
| 5 | jim | 23 | 091 |
| 6 | jim | 23 | 090 |
I have tried this query:
INSERT INTO temp_table
SELECT
DISTINCT #key_id,
name,
name_id,
#data_id FROM table1,
I am trying to dedupe a table by all fields in a row.
My desired output:
| key_id | name | name_id | data_id |
+--------+-------+---------+---------+
| 1 | jim | 23 | 098 |
| 2 | joe | 24 | 098 |
| 3 | john | 25 | 098 |
| 4 | jack | 26 | 098 |
What I'm actually getting:
| key_id | name | name_id | data_id |
+--------+-------+---------+----------+
| 1 | jim | 23 | NULL |
| 2 | joe | 24 | NULL |
| 3 | john | 25 | NULL |
| 4 | jack | 26 | NULL |
I am able to dedupe the table, but I am setting the 'data_Id' value to NULL by attempting to override the field with '#'
Is there anyway to select distinct on all fields and while keeping the value for 'data_id'? I will take the highest or MAX data_id # if possible.
If you only want one row returned for a specific value (in this case, name), one option you have is to group by that value. This seems like a good approach because you also said you wanted the largest data_id for each name, so I would suggest grouping and using the MAX() aggregate function like this:
SELECT name, name_id, MAX(data_id) AS data_id
FROM myTable
GROUP BY name, name_id;
The only thing you should be aware of is the possibility that a name occurs multiple times under different name_ids. If that is possible in your table, you could group by the name_id too, which is what I did.
Since you stated you're not interested in the key_id but only the name, I just excluded it from the query altogether to get this:
| name | name_id | data_id |
+-------+---------+---------+
| jim | 23 | 098 |
| joe | 24 | 098 |
| john | 25 | 098 |
| jack | 26 | 098 |
Here is the SQL Fiddle example.
RENAME TABLE myTable to Old_mytable,
myTable2 to myTable
INSERT INTO myTable
SELECT *
FROM Old_myTable
GROUP BY name, name_id;
This groups my tables by the values I want to dedupe while still keeping structure and ignoring the 'Data_id' column