I received a CSV file and one of the columns has names like Jack,Clark,James in one cell. Another will just have James, then another with be Clark,James. Is there a way I can GROUP BY and COUNT(*) without giving them all their own rows?
Ignoring for a moment the old adage that says "just because you can do something, it doesn't mean that you should", and noting the presence of a PRIMARY KEY in my data set, which is absent from yours...
SELECT * FROM ints;
+---+
| i |
+---+
| 0 |
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
| 7 |
| 8 |
| 9 |
+---+
SELECT * FROM my_table;
+----+--------------------+
| id | names |
+----+--------------------+
| 1 | steve,james,carlos |
| 2 | james |
| 3 | carlos,steve |
| 4 | james,jack |
+----+--------------------+
SELECT name
, COUNT(*) total
FROM
( SELECT DISTINCT id
, SUBSTRING_INDEX(SUBSTRING_INDEX(names,',',i),',',-1) name
FROM my_table x
, ints
) a
GROUP
BY name;
+--------+-------+
| name | total |
+--------+-------+
| | 4 |
| carlos | 2 |
| jack | 1 |
| james | 3 |
| steve | 2 |
+--------+-------+
Related
There are two tables,
Table A has a three-level structure that looks like
| id | name | level | up_level_id |
| :------- | :-------: | :------: | ----------:|
| 1 | lv1_name1 | 1 | null |
| 2 | lv1_name2 | 1 | null |
| 3 | lv2_name1 | 2 | 1 |
| 4 | lv2_name2 | 2 | 2 |
| 5 | lv3_name1 | 3 | 3 |
| 6 | lv3_name2 | 3 | 3 |
| 7 | lv3_name3 | 3 | 4 |
| 8 | lv3_name4 | 3 | 4 |
Table B looks like
| amount | org_id |
| -------- | -------- |
| 12,000 | 5 |
| 15,000 | 6 |
| 20,000 | 7 |
| 18,000 | 8 |
Table A and Table B can be joined on A.id=B.org_id, but they are all at the level-3 of Table A（Only level-3 has their amount）
I want to query the top-level name,level-1 name, and the summary amount that looks like
| sum_amount | top_lvl_name |
| -------- | -------- |
| 27,000 | lv1_name1 |
| 38,000 | lv1_name2 |
For Testing, I have already accomplished the query of the level-1 name from the level-3 id in TableA
The SQL is as follows
SELECT name
FROM TableA
WHERE id IN (
SELECT up_level_id
FROM Table A
WHERE id IN (
SELECT up_level_id
FROM Table A
WHERE id=5) --query the id:5's top-level name
);
But when I join these two tables as follows, it goes wrong
SELECT sum(amount) AS sum_amount, name AS top_lvl_name
FROM TableA, TableB
WHERE id = org_id
AND id IN (
SELECT up_level_id
FROM TableA
WHERE id IN (
SELECT up_level_id
FROM TableA
WHERE TableA.id IN(
SELECT org_id
FROM TABLEB
)
)
);
I get nothing as above
What can I do to make this query to be correct?
Thanks for everyone's answer and comment.
Finally, I find it very difficult to query the result as I wish. So, I've come up with a shortcut——create a new table that a three-level structure recorded horizontally, which looks like
| lv1_id | lv2_name | lv2_id | lv2_name | lv3_id | lv3_name |
| :------- | :-------: | :------: | :----------:| :------: | :----------:|
| 1 | lv1_name1 | 3 | lv2_name1 | 5 | lv3_name1 |
| 1 | lv1_name1 | 3 | lv2_name1 | 6 | lv3_name2 |
| 2 | lv1_name2 | 4 | lv2_name1 | 7 | lv3_name3 |
| 2 | lv1_name2 | 4 | lv2_name1 | 8 | lv3_name4 |
As above,I can easily connect two tables
Say I have a table like this:
+--------+-------+
| ID | LETTER|
+--------+-------+
| 1 | A |
| 1 | A |
| 1 | A |
| 2 | A |
| 2 | B |
| 3 | C |
| 3 | D |
| 4 | D |
+--------+-------+
How would I implement a query that returns the ID followed by how many unique letters it has? So it would look like this:
+--------+-------+
| ID | LETTER|
+--------+-------+
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 1 |
+--------+-------+
I've tried using group by but I cant figure it out.
You should search for the answer before questioning. But here is what you need:
SELECT yt.ID, COUNT(DISTINCT yt.LETTER)
FROM yourtable yt
GROUP BY yt.ID
I'm working on a query where I need to count distinct CarId row when the column LocationId is not null and get all CarId if its null or 0 but the query that I tried distincts all the CarId even if its null
#LocId int
Select Count(distinct a.CarId) from VehicleDetails a
inner join VehicleDocuments b on a.DocId=b.DocId
left join VehicleShipmentDetails dpg on dpg.VehicleShipmentId= b.VehicleShipmentId
where b.LogicalDelete=0 and a.LogicalDelete=0
and (dpg.LocationId= #LocId or dpg.LocationId= 0 or dpg.LocationId is null)
| ID | CarId | LocationId | DateCreated |
|------+----------------+-----------------+---------------|
| 1 | 1 | 5 | 02/03/2019 |
| 2 | 2 | null | 01/14/2019 |
| 3 | 2 | 0 | 02/03/2019 |
| 4 | 2 | 5 | 12/30/2018 |
| 5 | 4 | 3 | 01/10/2019 |
| 6 | 3 | 5 | 02/14/2019 |
| 7 | 2 | 5 | 03/13/2019 |
Desired output:
| ID | CarId | LocationId | DateCreated |
+------+----------------+-----------------+---------------+
| 1 | 1 | 5 | 02/03/2019 |
| 2 | 2 | null | 01/14/2019 |
| 3 | 2 | 0 | 02/03/2019 |
| 4 | 2 | 5 | 03/13/2019 |
| 5 | 4 | 3 | 01/10/2019 |
| 6 | 3 | 5 | 02/14/2019 |
Current Output
| ID | CarId | LocationId | DateCreated |
+------+----------------+-----------------+---------------+
| 1 | 1 | 5 | 02/03/2019 |
| 2 | 2 | 5 | 01/14/2019 |
| 3 | 4 | 3 | 01/10/2019 |
| 4 | 3 | 5 | 02/14/2019 |
Im getting a count of 4 but i needed to have 6 as the Count
EDIT: My goal is to remove the row to Distinct CarId if the value of the LocationId is Null or 0 but on my Current code, It distincts all CarId that is null,0 and equals to #LocId
You can query something like this, replace your_table by your actual set of data.
SELECT ID, CardId, LocationId, DateCreated
FROM your_table as T
WHERE NOT EXISTS (SELECT *
FROM your_table as T1
WHERE T.ID > T1.ID AND T.CarID = T1.CarID)
In SQL, you can use the statement CASE to manage conditions (just like the "if then else" in other programming languages). In your case this function could help because you have two differents cases to handle.
I have a complicated ordering issue in my query.
Raw, Unordered Data:
+------+--------+-----------+
| id | job_id | action_id |
+------+--------+-----------+
| 1 | 2 | 1 |
| 2 | 2 | 2 |
| 3 | 1 | 1 |
| 4 | 2 | 3 |
| 5 | 4 | 1 |
| 6 | 1 | 2 |
| 7 | 3 | 1 |
| 8 | 3 | 2 |
| 9 | 4 | 2 |
+------+--------+-----------+
Required Ordering:
+------+--------+-----------+
| id | job_id | action_id |
+------+--------+-----------+
| 7 | 3 | 1 |
| 8 | 3 | 2 |
| | | | * blank lines added for clarity,
| 5 | 4 | 1 | not desired in actual data
| 9 | 4 | 2 |
| | | |
| 3 | 1 | 1 |
| 6 | 1 | 2 |
| | | |
| 1 | 2 | 1 |
| 2 | 2 | 2 |
| 4 | 2 | 3 |
+------+--------+-----------+
The theory behind this ordering:
the largest id is the most recently added entry
the most recent id with action_id of 1
followed by the entries with ascending action_ids that have the same job_id
then the next most recent action_id of 1
ad infinitum
EDIT: I'm not able to add columns to the table in order to aid in sorting, as I've seen in some other solutions to ordering questions.
Any help is greatly appreciated!
My best shot is this:
SELECT * FROM tbl
ORDER BY FIND_IN_SET(job_id,
(SELECT GROUP_CONCAT(job_id ORDER BY ID DESC)
FROM tbl WHERE action_id = 1));
I didn't find a way to do it easily, What do you think of the following code :
select c.id, c.job_id, c.action_id
from (select a.id, a.job_id, a.action_id, min(b.id) as related_id
from myTable a
inner join myTable b
on a.job_id=b.job_id
group by a.job_id) c
group by c.id
order by c.related_id desc, c.action_id
I am trying to write a MySQL query that retrieves one record from table "projects" that has a one-to-many relationship with table "tags". My application uses 4 tables to do this:
Projects - the projects table
Entities - entity table; references several application resources
Tags - tags table
Tag_entity - links tags to entities
Is it possible to write the query in such a way that multiple values from table "Tags" are concatenated into one result column? I'd prefer doing this without using subqueries.
Table clarification:
-------------
| Tag_Entity |
------------- ---------- | ----------- | -------
| Projects | | Entities | | - id | | Tags |
| ----------- | | -------- | | - tag_id | | ----- |
| - id | --> | - id | --> | - entity_id | --> | id |
| - entity_id | ---------- ------------- | name |
------------- -------
Desired result:
Projects.id Entities.id Tags.name (concatenated)
1 5 'foo','bar','etc'
see GROUP_CONCAT
example:
mysql> SELECT * FROM blah;
+----+-----+-----------+
| K | grp | name |
+----+-----+-----------+
| 1 | 1 | foo |
| 2 | 1 | bar |
| 3 | 2 | hydrogen |
| 4 | 4 | dasher |
| 5 | 2 | helium |
| 6 | 2 | lithium |
| 7 | 4 | dancer |
| 8 | 3 | winken |
| 9 | 4 | prancer |
| 10 | 2 | beryllium |
| 11 | 1 | baz |
| 12 | 3 | blinken |
| 13 | 4 | vixen |
| 14 | 1 | quux |
| 15 | 4 | comet |
| 16 | 2 | boron |
| 17 | 4 | cupid |
| 18 | 4 | donner |
| 19 | 4 | blitzen |
| 20 | 3 | nod |
| 21 | 4 | rudolph |
+----+-----+-----------+
21 rows in set (0.00 sec)
mysql> SELECT grp, GROUP_CONCAT(name ORDER BY K) FROM blah GROUP BY grp;
+-----+----------------------------------------------------------------+
| grp | GROUP_CONCAT(name ORDER BY K) |
+-----+----------------------------------------------------------------+
| 1 | foo,bar,baz,quux |
| 2 | hydrogen,helium,lithium,beryllium,boron |
| 3 | winken,blinken,nod |
| 4 | dasher,dancer,prancer,vixen,comet,cupid,donner,blitzen,rudolph |
+-----+----------------------------------------------------------------+
4 rows in set (0.00 sec)
I don't know if it works in MySQL, but in SQL Server you can use a trick for this:
DECLARE #csv varchar(max)
SET #csv = ''
SELECT #csv = #csv + ',' + foo.SomeColumn
FROM [FOO] foo
WHERE foo.SomeId = #SomeId
Then in the main select
SELECT ..., #csv AS [Tags]
FROM ...
The result of SELECT #csv = #csv + ',' + foo.SomeColumn line is that #csv becomes the comma-separated list of all matching records from the source table (after predicate).
Worth trying in MySQL?