I'm trying to compose an SQLite query and I've found a problem that's beyond my skillset. I'm trying to output columns that are based on the rows of another referenced table.
Food_List:
| food_id | name |
|---------|-----------|
| 1 | Apple |
| 2 | Orange |
| 3 | Pear |
Nutrient_Definition:
| nutrient_id | name |
|-------------|-----------|
| 21 | Carbs |
| 22 | Protein |
| 23 | Fat |
Nutrient_Data:
| food_id | nutrient_id | value |
|---------|-------------|-------|
| 1 | 21 | 50 |
| 1 | 22 | 24 |
| 1 | 23 | 63 |
| 2 | 22 | 12 |
| 2 | 23 | 95 |
| 3 | 21 | 66 |
| 3 | 22 | 87 |
| 3 | 23 | 38 |
Output:
| food_id | name | Carbs | Protein | Fat |
|---------|-----------|-------|---------|-----|
| 1 | Apple | 50 | 24 | 63 |
| 2 | Orange | | 12 | 95 |
| 3 | Pear | 66 | 87 | 38 |
(Note that Orange does not have a "Carbs" entry in the Nutrient_Data table)
I believe the following will do what you want :-
DROP TABLE IF EXISTS food_list;
CREATE TABLE IF NOT EXISTS food_list(food_id INTEGER PRIMARY KEY, name TEXT);
DROP TABLE IF EXISTS nutrient_definition;
CREATE TABLE IF NOT EXISTS nutrient_definition(nutrient_id INTEGER PRIMARY KEY, name TEXT);
DROP TABLE IF EXISTS nutrient_data;
CREATE TABLE IF NOT EXISTS nutrient_data(food_id INTEGER, nutrient_id INTEGER, value INTEGER);
INSERT INTO food_list (name) VALUES
('apple'),('orange'),('pear')
;
INSERT INTO nutrient_definition (name) VALUES
('carbs'),('protien'),('fat')
;
INSERT INTO nutrient_data VALUES
(1,1,50),(1,2,24),(1,3,63),
(2,2,12),(2,3,95),
(3,1,66),(3,2,87),(3,3,38)
;
SELECT food_list.food_id,food_list.name,
(
SELECT value
FROM nutrient_data
WHERE nutrient_data.food_id = food_list.food_id AND
nutrient_data.nutrient_id = (SELECT nutrient_definition.nutrient_id FROM nutrient_definition WHERE nutrient_definition.name = 'carbs')
),
(
SELECT value
FROM nutrient_data
WHERE nutrient_data.food_id = food_list.food_id AND
nutrient_data.nutrient_id = (SELECT nutrient_definition.nutrient_id FROM nutrient_definition WHERE nutrient_definition.name = 'protien')
),
(
SELECT value
FROM nutrient_data
WHERE nutrient_data.food_id = food_list.food_id AND
nutrient_data.nutrient_id = (SELECT nutrient_definition.nutrient_id FROM nutrient_definition WHERE nutrient_definition.name = 'fat')
)
FROM food_list
;
Results in :-
Related
I have a source like below table:
+---------+--+--------+--+---------+--+--+------+
| ID | | SEQ_NO | | UNIT_ID | | | D_ID |
+---------+--+--------+--+---------+--+--+------+
| 7979092 | | 1 | | 99 | | | 759 |
| 7979092 | | 2 | | -1 | | | 869 |
| 7979092 | | 3 | | -1 | | | 927 |
| 7979092 | | 4 | | -1 | | | 812 |
| 7979092 | | 5 | | 99 | | | 900 |
| 7979092 | | 6 | | 99 | | | 891 |
| 7979092 | | 7 | | -1 | | | 785 |
| 7979092 | | 8 | | -1 | | | 762 |
| 7979092 | | 9 | | -1 | | | 923 |
+---------+--+--------+--+---------+--+--+------+
I have to merge the rows when consecutive unit_id has same value. We should take max(D_id) when we consolidate the rows. Expected output is:
+---------+---------+------+
| ID | UNIT_ID | D_ID |
+---------+---------+------+
| 7979092 | 99 | 759 |
| 7979092 | -1 | 927 |
| 7979092 | 99 | 900 |
| 7979092 | -1 | 923 |
+---------+---------+------+
I have tried to find the solution using Teradata ordered analytical function, but did not find the solution. I use Teradata 16.
Thank You.
This logic is a bit quirky, it's based on two sequences created by different sort orders:
SELECT
ID
,UNIT_ID
,Max(D_ID)
FROM
(
SELECT
ID
,SEQ_NO
,UNIT_ID
,D_ID
-- assign the same value to consecutive UNIT_IDs
,SEQ_NO -
Row_Number()
Over(PARTITION BY ID, UNIT_ID
ORDER BY SEQ_NO) AS grp
FROM tab
) AS dt
GROUP BY 1,2,grp
You can use RESET WHEN to dynamically create groups within the window. Here's one way to do it:
select ID, UNIT_ID,
max(D_ID) over(
partition by ID order by SEQ_NO
reset when UNIT_ID <> UNIT_ID_prev -- Create new group for new value
) as D_ID
from (
select ID, SEQ_NO, UNIT_ID, D_ID,
lag(UNIT_ID) over(partition by ID order by SEQ_NO) as UNIT_ID_prev -- Previous value
from MY_TABLE
) src
qualify row_number() over(
partition by ID order by SEQ_NO
reset when UNIT_ID <> UNIT_ID_prev -- Match original max() window
) = 1 -- One row per group (similar to DISTINCT)
I have a SQLite table just like this:
the table name is 'surat'
But i want to make id_ayat to be split into different rows using SQLite query, and expected result just like this:
_id|id_surat|id_ayat
---+--------+-------
3 | 2 | 112
3 | 2 | 213
3 | 3 | 19
3 | 3 | 83
3 | 3 | 85
3 | 3 | 102
is that possible? what query that i can use in SQLite format?
With a recursive CTE:
with recursive cte as (
select _id, id_surat, id_ayat,
id_ayat + 0 col
from tablename
union all
select _id, id_surat, trim(substr(id_ayat, length(col) + 2)),
trim(substr(id_ayat, length(col) + 2)) + 0
from cte
where instr(id_ayat, ',')
)
select _id, id_surat, col id_ayat
from cte
order by _id, id_surat
See the demo.
Results:
| _id | id_surat | id_ayat |
| --- | -------- | ------- |
| 3 | 2 | 112 |
| 3 | 2 | 213 |
| 3 | 3 | 19 |
| 3 | 3 | 83 |
| 3 | 3 | 85 |
| 3 | 3 | 102 |
I'm working with SQL Server and I have this 3 tables
STUDENTS
| id | student |
-------------
| 1 | Ronald |
| 2 | Jenny |
SCORES
| id | score | period | student |
| 1 | 8 | 1 | 1 |
| 2 | 9 | 2 | 1 |
PERIODS
| id | period |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
And I want a query that returns this result:
| student | score1 | score2 | score3 | score4 |
| Ronald | 8 | 9 | null | null |
| Jenny | null | null | null | null |
As you can see, the number of scores depends of the periods because sometimes it can be 4 o 3 periods.
I don't know if I have the wrong idea or should I make this in the application, but I want some help.
You need to PIVOT your data e.g.
select Y.Student, [1], [2], [3], [4]
from (
select T.Student, P.[Period], S.Score
from Students T
cross join [Periods] P
left join Scores S on S.[Period] = P.id and S.Student = T.id
) X
pivot
(
sum(Score)
for [Period] in ([1],[2],[3],[4])
) Y
Reference: https://learn.microsoft.com/en-us/sql/t-sql/queries/from-using-pivot-and-unpivot?view=sql-server-20
I have the following table in an sqlite database
+----+-------------+-------+
| ID | Week Number | Count |
+----+-------------+-------+
| 1 | 1 | 31 |
| 2 | 2 | 16 |
| 3 | 3 | 73 |
| 4 | 4 | 59 |
| 5 | 5 | 44 |
| 6 | 6 | 73 |
+----+-------------+-------+
I want to get the following table out. Where I get this weeks sales as one column and then the next column will be last weeks sales.
+-------------+-----------+-----------+
| Week Number | This_Week | Last_Week |
+-------------+-----------+-----------+
| 1 | 31 | null |
| 2 | 16 | 31 |
| 3 | 73 | 16 |
| 4 | 59 | 73 |
| 5 | 44 | 59 |
| 6 | 73 | 44 |
+-------------+-----------+-----------+
This is the select statement i was going to use:
select
id, week_number, count,
(select count from tempTable
where week_number = (week_number-1))
from
tempTable;
You are comparing values in two different rows. When you are just writing week_number, the database does not know which one you mean.
To refer to a column in a specific table, you have to prefix it with the table name: tempTable.week_number.
And if both tables have the same name, you have to rename at least one of them:
SELECT id,
week_number,
count AS This_Week,
(SELECT count
FROM tempTable AS T2
WHERE T2.week_number = tempTable.week_number - 1
) AS Last_Week
FROM tempTable;
In case of you want to take a query upon a same table twice, you have to put aliases on the original one and its replicated one to differentiate them
select a.week_number,a.count this_week,
(select b.count from tempTable b
where b.week_number=(a.week_number-1)) last_week
from tempTable a;
I have a table like this:
+----+----------+----------+----------+-----------+----------+----------+
| ID | AR_SCORE | ER_SCORE | FS_SCORE | CPF_SCORE | IF_SCORE | IS_SCORE |
+----+----------+----------+----------+-----------+----------+----------+
| 1 | 25 | 35 | 45 | 55 | 65 | 75 |
| 2 | 95 | 85 | 75 | 65 | 55 | 45 |
+----+----------+----------+----------+-----------+----------+----------+
And I need to extract this:
+----+----------+-------+
| ID | SCORE | VALUE |
+----+----------+-------+
| 1 | AR_SCORE | 25 |
| 1 | ER_SCORE | 35 |
| 2 | AR_SCORE | 95 |
+----+----------+-------+
I read many questions about how to use pivoting in oracle but I could not make it work.
The conversion from columns into rows is actually an UNPIVOT. Since you are using Oracle 11g there are a few ways that you can get the result.
The first way would be using a combination of SELECT yourcolumn FROM...UNION ALL:
select ID, 'AR_SCORE' as Score, AR_SCORE as value
from yourtable
union all
select ID, 'ER_SCORE' as Score, ER_SCORE as value
from yourtable
union all
select ID, 'FS_SCORE' as Score, FS_SCORE as value
from yourtable
union all
select ID, 'IF_SCORE' as Score, IF_SCORE as value
from yourtable
union all
select ID, 'IS_SCORE' as Score, IS_SCORE as value
from yourtable
order by id
See Demo. Using UNION ALL was how you needed to unpivot data prior to Oracle 11g, but starting in that version the UNPIVOT function was implemented. This will get you the same result with fewer lines of code:
select ID, Score, value
from yourtable
unpivot
(
value
for Score in (AR_SCORE, ER_SCORE, FS_SCORE, IF_SCORE, IS_SCORE)
) un
order by id
See Demo. Both will give a result:
| ID | SCORE | VALUE |
|----|----------|-------|
| 1 | AR_SCORE | 25 |
| 1 | FS_SCORE | 45 |
| 1 | IS_SCORE | 75 |
| 1 | IF_SCORE | 65 |
| 1 | ER_SCORE | 35 |
| 2 | FS_SCORE | 75 |
| 2 | IS_SCORE | 45 |
| 2 | ER_SCORE | 85 |
| 2 | IF_SCORE | 55 |
| 2 | AR_SCORE | 95 |