I need to select some rows from second table and concatenate them in comma-separated string. Query works well except one problem - It always selects all rows and ignores LIMIT.
This is part of my query which gets that string and ignores LIMIT:
select
group_concat(value order by `order` asc SEPARATOR ', ')
from slud_data
left join slud_types on slud_types.type_id=slud_data.type_id
where slud_data.product_id=18 and value!='' and display=0 limit 3;
// Result:
+---------------------------------------------------------+
| group_concat(value order by `order` asc SEPARATOR ', ') |
+---------------------------------------------------------+
| GA-XXXX, Bentley, CONTINENTAL FLYING SPUR, 2006 |
+---------------------------------------------------------+
// Expected result: (only 3 comma-separated records, not 4)
Full query:
SELECT *,product_id id,
(select group_concat(value order by `order` asc SEPARATOR ', ') from slud_data left join slud_types on slud_types.type_id=slud_data.type_id where slud_data.product_id=t1.product_id and value!='' and display=0 limit 3) text
FROM slud_products t1
WHERE
now() < DATE_ADD(date,INTERVAL +ttl DAY) and activated=1
ORDER BY t1.date desc
The LIMIT clause limits the number of rows in the final result set, not the number of rows used to construct the string in the GROUP_CONCAT. Since your query returns only one row in the final result the LIMIT has no effect.
You can solve your issue by constructing a subquery with LIMIT 3, then in an outer query apply GROUP_CONCAT to the result of that subquery.
Your query is not working as you intended for the reasons #Mark Byers outlined in the other answer. You may want to try the following instead:
SELECT GROUP_CONCAT(`value` ORDER BY `order` ASC SEPARATOR ', ')
FROM (
SELECT `value`, `order`
FROM slud_data
LEFT JOIN slud_types ON slud_types.type_id = slud_data.type_id
WHERE slud_data.product_id = 18 AND value != '' AND display = 0
LIMIT 3
) a;
An example of Mark Byers idea:
SELECT GROUP_CONCAT(id, '|', name)
FROM (
SELECT id, name
FROM users
LIMIT 3) inner
Related
I am trying to unnest the below table .
Using the below unnest query to flatten the table
SELECT
id,
name ,keyword
FROM `project_id.dataset_id.table_id`
,unnest (`groups` ) as `groups`
where id = 204358
Problem is , this duplicates the rows (except name) as is the case with flattening the table.
How can I modify the query to put the names in two different columns rather than rows.
Expected output below -
That's because the comma is a cross join - in combination with an unnested array it is a lateral cross join. You repeat the parent row for every row in the array.
One problem with pivoting arrays is that arrays can have a variable amount of rows, but a table must have a fixed amount of columns.
So you need a way to decide for a certain row that becomes a certain column.
E.g. with
SELECT
id,
name,
groups[ordinal(1)] as firstArrayEntry,
groups[ordinal(2)] as secondArrayEntry,
keyword
FROM `project_id.dataset_id.table_id`
unnest(groups)
where id = 204358
If your array had a key-value pair you could decide using the key. E.g.
SELECT
id,
name,
(select value from unnest(groups) where key='key1') as key1,
keyword
FROM `project_id.dataset_id.table_id`
unnest(groups)
where id = 204358
But that doesn't seem to be the case with your table ...
A third option could be PIVOT in combination with your cross-join solution but this one has restrictions too: and I'm not sure how computation-heavy this is.
Consider below simple solution
select * from (
select id, name, keyword, offset
from `project_id.dataset_id.table_id`,
unnest(`groups`) with offset
) pivot (max(name) name for offset + 1 in (1, 2))
if applied to sample data in your question - output is
Note , when you apply to your real case - you just need to know how many such name_NNN columns to expect and extend respectively list - for example for offset + 1 in (1, 2, 3, 4, 5)) if you expect 5 such columns
In case if for whatever reason you want improve this - use below where everything is built dynamically for you so you don't need to know in advance how many columns it will be in the output
execute immediate (select '''
select * from (
select id, name, keyword, offset
from `project_id.dataset_id.table_id`,
unnest(`groups`) with offset
) pivot (max(name) name for offset + 1 in (''' || string_agg('' || pos, ', ') || '''))
'''
from (select pos from (
select max(array_length(`groups`)) cnt
from `project_id.dataset_id.table_id`
), unnest(generate_array(1, cnt)) pos
))
Your question is a little unclear, because it does not specify what to do with other keywords or other columns. If you specifically want the first two values in the array for keyword "OVG", you can unnest the array and pull out the appropriate names:
SELECT id,
(SELECT g.name
FROM UNNEST(t.groups) g WITH OFFSET n
WHERE key = 'OVG'
ORDER BY n
LIMIT 1
) as name_1,
(SELECT g.name
FROM UNNEST(t.groups) g WITH OFFSET n
WHERE key = 'OVG'
ORDER BY n
LIMIT 1 OFFSET 1
) as name_2,
'OVG' as keyword
FROM `project_id.dataset_id.table_id` t
WHERE id = 204358;
I'm using the following code to try to return the average revenue based on the number of songs in an album.
WITH Album_Tracks AS (
SELECT COUNT(*) AS "#ofTracks", SUM(invoice_items.UnitPrice) AS "Album_Revenue"
from tracks
LEFT JOIN invoice_items ON invoice_items.trackID = tracks.trackID
GROUP BY Albumid
)
SELECT #ofTracks, AVG(Album_Revenue)
FROM Album_Tracks
GROUP BY #ofTracks
ORDER BY #ofTracks DESC
The problem I am running into is that the "# of tracks" column in the temporary table 'Album_Tracks' returns a column of NULL values when i don't select all data from the table.
As in, doing this: SELECT * FROM Album_Tracks returns values, but SELECT #ofTracks FROM Album_Tracks returns only null values.
I'm not sure what the problem in my code is.
Expecting to see:
Example 1
But am getting:
Example 2
First example the order by was not included.
just a suggestion
try avoid not allowed char ( in table and column name) as + - ? ! * # % ^ & # = / \ : " '
WITH Album_Tracks AS (
SELECT COUNT(*) AS NumOfTracks
, SUM(invoice_items.UnitPrice) AS Album_Revenue
from tracks
LEFT JOIN invoice_items ON invoice_items.trackID = tracks.trackID
GROUP BY Albumid
)
SELECT NumOfTracks, AVG(Album_Revenue) F
ROM Album_Tracks
GROUP BY NumOfTracks
ORDER BY NumOfTracks DESC
Try just a simple:
SELECT #ofTracks
It will return NULL.
Enclose #ofTracks in double quotes, or backticks or square brackets:
SELECT "#ofTracks", AVG(Album_Revenue) FROM Album_Tracks
GROUP BY "#ofTracks"
ORDER BY "#ofTracks" DESC
I want to write a query which will display the following result
FROM
ID Contract# Market
1 123kjs 40010
1 123kjs 40011
2 121kjs 40098
2 121kjs 40099
TO
ID Contract# Market
1 123kjs 40010,40011
2 121kjs 40098,40099
Try out this query, I use GROUP_CONCAT to turn column fields into 1 row field.
Also notice that you should rename the FROM clause with the name of your table.
SELECT ID,Contract#, GROUP_CONCAT(Market SEPARATOR ',')
FROM nameOfThatTable GROUP BY ID;
Try this out. I used PIVOT to solve it.
SELECT
ID,
Contract#,
ISNULL(CONVERT(varchar,[40010]) + ',' + CONVERT(varchar,[40011]),
CONVERT(varchar,[40098]) + ',' + CONVERT(varchar,[40099])) AS Market FROM
( SELECT * FROM ContractTable) AS A
PIVOT(MIN(Market) FOR Market IN ([40010],[40011],[40098],[40099])) AS PVT
ORDER BY ID
You can use ', ' + CAST(Market AS VARCHAR(30)) in sub-query and join Id and Contract# of sub-query with outer query to get values of Market as Comma Separated Values for each Id and Contract#.
SELECT DISTINCT ID,Contract#,
SUBSTRING(
(SELECT ', ' + CAST(Market AS VARCHAR(30))
FROM #TEMP T1
WHERE T2.Id=T1.Id AND T2.Contract#=T1.Contract#
FOR XML PATH('')),2,200000) Market
FROM #TEMP T2
Click here to view result
Note
.........
If you want to get CSV values for Id only, remove T2.Contract#=T1.Contract# from sub-query.
My problem requires me to query data from the table, and include a column to calculate the % increase as well. I need to pull only the records with the highest % of increase using MAX. I think I'm on the right track but but for some reason its returning all records despite the having clause calling for just the max.
Select
O.Grocery_Item,
TO_CHAR(sum(g.Price_IN_2000), '$99,990.00') TOTAL_IN_2000,
TO_CHAR(sum(g.Estimated_Price_In_2025), '$99,990.00') TOTAL_IN_2025,
TO_CHAR(Round(O.MY_OUTPUT),'9,990') || '%' as My_Output
From
GROCERY_PRICES g,
(SELECT
GROCERY_ITEM,
(((sum(Estimated_Price_In_2025) -
sum(Price_IN_2000))/sum(Price_IN_2000))*100) MY_OUTPUT
FROM
GROCERY_PRICES
GROUP BY GROCERY_ITEM) O
Where
G.GROCERY_ITEM = O.GROCERY_ITEM
GROUP BY
O.GROCERY_ITEM, O.MY_OUTPUT
Having
my_output IN (select Max(O.MY_OUTPUT) from GROCERY_PRICES);
Results:
GROCERY_ITEM TOTAL_IN_2000 TOTAL_IN_2025 MY_OUTPUT
------------------------------ ------------- ------------- ---------
M_004 $2.70 $5.65 109%
B_001 $0.80 $2.64 230%
T_006 $5.70 $6.65 17%
B_002 $2.72 $7.36 171%
E_001 $0.62 $1.78 187%
R_003 $4.00 $13.20 230%
6 rows selected
You can simplify your query so you only select from the Groceries table once since your My_Output column is only a function of numbers you are already producing the self join is not necessary. Then I've used RANK to get the top records (although if you are not concerned about ties ROWNUM will work better):
SELECT g.Grocery_Item,
g.TOTAL_IN_2000,
g.TOTAL_IN_2025,
g.My_Output
FROM ( SELECT Grocery_Item,
TO_CHAR(TOTAL_IN_2000, '$99,990.00') TOTAL_IN_2000,
TO_CHAR(TOTAL_IN_2025, '$99,990.00') TOTAL_IN_2025,
TO_CHAR(ROUND(((TOTAL_IN_2025 / TOTAL_IN_2000) - 1) * 100), '9,990') || '%' as My_Output,
RANK() OVER(PARTITION BY Grocery_Item ORDER BY (TOTAL_IN_2025 / TOTAL_IN_2000) - 1 DESC) AS GroceryRank
FROM ( SELECT g.Grocery_Item,
SUM(g.Price_IN_2000) TOTAL_IN_2000,
SUM(g.Estimated_Price_In_2025) TOTAL_IN_2025
FROM GROCERY_PRICES g
GROUP BY g.Grocery_Item
) g
) g
WHERE GroceryRank = 1;
I've also simplified your percentage calculation.
Try this instead:
select *
from (Select O.Grocery_Item, TO_CHAR(sum(g.Price_IN_2000), '$99,990.00') TOTAL_IN_2000,
TO_CHAR(sum(g.Estimated_Price_In_2025), '$99,990.00') TOTAL_IN_2025,
TO_CHAR(Round(O.MY_OUTPUT),'9,990') || '%' as My_Output
From GROCERY_PRICES g join
(SELECT GROCERY_ITEM,
(((sum(Estimated_Price_In_2025) -
sum(Price_IN_2000))/sum(Price_IN_2000))*100
) MY_OUTPUT
FROM GROCERY_PRICES
GROUP BY GROCERY_ITEM
) O
on G.GROCERY_ITEM = O.GROCERY_ITEM
GROUP BY O.GROCERY_ITEM, O.MY_OUTPUT
ORDER BY my_output desc
) t
where rownum = 1
The problem is that your subquery only has outer references. So, the o.my_output is coming from the outer table, not the from clause in the subquery. You are comparing a value to itself, which for non-NULL values is always true.
Since you want the maximum value, the easiest way is to order the list and take the first row. You can also do this with analytic functions, but rownum is usually more efficient.
With the following MySQL table:
+-----------------------------+
+ id INT UNSIGNED +
+ name VARCHAR(100) +
+-----------------------------+
How can I select a single row AND its position amongst the other rows in the table, when sorted by name ASC. So if the table data looks like this, when sorted by name:
+-----------------------------+
+ id | name +
+-----------------------------+
+ 5 | Alpha +
+ 7 | Beta +
+ 3 | Delta +
+ ..... +
+ 1 | Zed +
+-----------------------------+
How could I select the Beta row getting the current position of that row? The result set I'm looking for would be something like this:
+-----------------------------+
+ id | position | name +
+-----------------------------+
+ 7 | 2 | Beta +
+-----------------------------+
I can do a simple SELECT * FROM tbl ORDER BY name ASC then enumerate the rows in PHP, but it seems wasteful to load a potentially large resultset just for a single row.
Use this:
SELECT x.id,
x.position,
x.name
FROM (SELECT t.id,
t.name,
#rownum := #rownum + 1 AS position
FROM TABLE t
JOIN (SELECT #rownum := 0) r
ORDER BY t.name) x
WHERE x.name = 'Beta'
...to get a unique position value. This:
SELECT t.id,
(SELECT COUNT(*)
FROM TABLE x
WHERE x.name <= t.name) AS position,
t.name
FROM TABLE t
WHERE t.name = 'Beta'
...will give ties the same value. IE: If there are two values at second place, they'll both have a position of 2 when the first query will give a position of 2 to one of them, and 3 to the other...
This is the only way that I can think of:
SELECT `id`,
(SELECT COUNT(*) FROM `table` WHERE `name` <= 'Beta') AS `position`,
`name`
FROM `table`
WHERE `name` = 'Beta'
If the query is simple and the size of returned result set is potentially large, then you may try to split it into two queries.
The first query with a narrow-down filtering criteria just to retrieve data of that row, and the second query uses COUNT with WHERE clause to calculate the position.
For example in your case
Query 1:
SELECT * FROM tbl WHERE name = 'Beta'
Query 2:
SELECT COUNT(1) FROM tbl WHERE name >= 'Beta'
We use this approach in a table with 2M record and this is way more scalable than OMG Ponies's approach.
The other answers seem too complicated for me.
Here comes an easy example, let's say you have a table with columns:
userid | points
and you want to sort the userids by points and get the row position (the "ranking" of the user), then you use:
SET #row_number = 0;
SELECT
(#row_number:=#row_number + 1) AS num, userid, points
FROM
ourtable
ORDER BY points DESC
num gives you the row postion (ranking).
If you have MySQL 8.0+ then you might want to use ROW_NUMBER()
The position of a row in the table represents how many rows are "better" than the targeted row.
So, you must count those rows.
SELECT COUNT(*)+1 FROM table WHERE name<'Beta'
In case of a tie, the highest position is returned.
If you add another row with same name of "Beta" after the existing "Beta" row, then the position returned would be still 2, as they would share same place in the classification.
Hope this helps people that will search for something similar in the future, as I believe that the question owner already solved his issue.
I've got a very very similar issue, that's why I won't ask the same question, but I will share here what did I do, I had to use also a group by, and order by AVG.
There are students, with signatures and socore, and I had to rank them (in other words, I first calc the AVG, then order them in DESC, and then finally I needed to add the position (rank for me), So I did something Very similar as the best answer here, with a little changes that adjust to my problem):
I put finally the position (rank for me) column in the external SELECT
SET #rank=0;
SELECT #rank := #rank + 1 AS ranking, t.avg, t.name
FROM(SELECT avg(students_signatures.score) as avg, students.name as name
FROM alumnos_materia
JOIN (SELECT #rownum := 0) r
left JOIN students ON students.id=students_signatures.id_student
GROUP BY students.name order by avg DESC) t
I was going through the accepted answer and it seemed bit complicated so here is the simplified version of it.
SELECT t,COUNT(*) AS position FROM t
WHERE name <= 'search string' ORDER BY name
I have similar types of problem where I require rank(Index) of table order by votes desc. The following works fine with for me.
Select *, ROW_NUMBER() OVER(ORDER BY votes DESC) as "rank"
From "category_model"
where ("model_type" = ? and "category_id" = ?)
may be what you need is with add syntax
LIMIT
so use
SELECT * FROM tbl ORDER BY name ASC LIMIT 1
if you just need one row..