SQLITE order by numeric and not alphabetic - sqlite

When I order my database SQLITE by Classement I have this :
Classement | Nom
1 | clem
10 | caro
11 | flo
12 | raph
2 | prisc
3 | karim
4 | prout
I would like to get :
Classement | Nom
1 | clem
2 | prisc
3 | karim
4 | prout
10 | caro
11 | flo
12 | raph
Here is my code :
SELECT t.Classement
FROM tableau t
WHERE 1 = (SELECT 1 + COUNT (*) FROM tableau t2 WHERE t2.Classement < t.Classement OR ( t2.Classement == t.Classement AND t2.Nom < t.Nom ))
Can anyone help me ?
Thank you!

I guess column Classement is not an integer but character. So try this:
SELECT * FROM tableau ORDER BY cast(Classement as integer);

You get alphabetic order if the values are strings.
To change the table so that all Classement values are numbers, ensure that the column type is not a text type, and use this:
UPDATE tableau SET Classement = CAST(Classement AS NUMBER);

Related

How to query dates using sqlite between

Im trying to query a range between dates but
i have tried using the date datatype,store the values in the date column as string and also use the date function but not getting the desired results
CREATE TABLE PvcTable (
date TEXT NOT NULL,
Wardname TEXT NOT NULL,
Puname TEXT NOT NULL,
PvcReceived TEXT,
PRIMARY KEY (
date,
Wardname,
Puname
)
);
the expected result is when i query let say
SELECT * from pvctable
where date between '2019-1-1' and '2019-12-1'
order by WARDNAME
i should get all the records between jan - dec 2019, but instead i get
this.only 3 records return.
date Wardname Puname PvcReceived
2019-10 01Alagarno 010KANGARWAPRISCHII 58
2019-11 02Baga 001MILEFOUR 58
2019-12 02Baga 002DARBASHATA 58
It is important to make sure that the dates in the table have the proper format YYYY-MM-DD which is comparable.
From the sample data you posted I see that there is no DD part in the dates, which is fine if you don't need it, because YYYY-MM is also comparable.
But if there is no DD part then in your query you should not compare the date column with dates containing this part, but with dates in the format YYYY-MM.
So change to this:
SELECT * from pvctable
where date between '2019-01' and '2019-12'
order by WARDNAME
See the demo.
Results:
| date | Wardname | Puname | PvcReceived |
| ------- | ---------- | ------------------- | ----------- |
| 2019-01 | 01Alagarno | 001ALAGARNOPRISCH | 58 |
| 2019-10 | 01Alagarno | 010KANGARWAPRISCHII | 58 |
| 2019-11 | 02Baga | 001MILEFOUR | 58 |
| 2019-12 | 02Baga | 002DARBASHATA | 58 |

'merge' rows if they are duplicated in a table - SQLite

Table is the following:
CREATE TABLE UserLog(uid TEXT, clicks INT, lang TEXT)
Where uid field should be unique.
Here is some sample data:
| uid | clicks | lang |
----------------------------------------
| "898187354" | 4 | "ru" |
| "898187354" | 4 | "ru" |
| "123456789" | 1 | <null> |
| "123456789" | 10 | "en" |
| "140922382" | 13 | <null> |
As you can see, I have multiple rows with where the uid field is now duplicated. I would like for those rows to be merged in a following way:
clicks fields are added, and lang fields are updated if their previous value was null.
For the data shown above, it would look something like this:
| uid | clicks | lang |
---------------------------------------
| "898187354" | 8 | "ru" |
| "123456789" | 11 | "en" |
| "140922382" | 13 | <null> |
It seems that I can find many ways to simply delete duplicate data, which I do not necessarily want to do. I'm unsure how I can introduce logic in SQL statements that does this.
First update:
update userlog
set
clicks = (select sum(u.clicks) from userlog u where u.uid = userlog.uid),
lang = (select max(u.lang) from userlog u where u.uid = userlog.uid)
where not exists (
select 1 from userlog u
where u.uid = userlog.uid and u.rowid < userlog.rowid
);
and then delete the duplicate rows that are not needed:
delete from userlog
where exists (
select 1 from userlog u
where u.uid = userlog.uid and u.rowid < userlog.rowid
);

SQLite find table row where a subset of columns satisfies a specified constraint

I have the following SQLite table
CREATE TABLE visits(urid INTEGER PRIMARY KEY AUTOINCREMENT,
hash TEXT,dX INTEGER,dY INTEGER,dZ INTEGER);
Typical content would be
# select * from visits;
urid | hash | dx | dY | dZ
------+-----------+-------+--------+------
1 | 'abcd' | 10 | 10 | 10
2 | 'abcd' | 11 | 11 | 11
3 | 'bcde' | 7 | 7 | 7
4 | 'abcd' | 13 | 13 | 13
5 | 'defg' | 20 | 21 | 17
What I need to do here is identify the urid for the table row which satisfies the constraint
hash = 'abcd' AND (nearby >= (abs(dX - tX) + abs(dY - tY) + abs(dZ - tZ))
with the smallest deviation - in the sense of smallest sum of absolute distances
In the present instance with
nearby = 7
tX = tY = tZ = 12
there are three rows that meet the above constraint but with different deviations
urid | hash | dx | dY | dZ | deviation
------+-----------+-------+--------+--------+---------------
1 | 'abcd' | 10 | 10 | 10 | 6
2 | 'abcd' | 11 | 11 | 11 | 3
4 | 'abcd' | 12 | 12 | 12 | 3
in which case I would like to have reported urid = 2 or urid = 3 - I don't actually care which one gets reported.
Left to my own devices I would fetch the full set of matching rows and then dril down to the one that matches my secondary constraint - smallest deviation - in my own Java code. However, I suspect that is not necessary and it can be done in SQL alone. My knowledge of SQL is sadly too limited here. I hope that someone here can put me on the right path.
I now have managed to do the following
CREATE TEMP TABLE h1(v1 INTEGER,v2 INTEGER);
SELECT urid,(SELECT (abs(dX - 12) + abs(dY - 12) + abs(dZ - 12))) devi FROM visits WHERE hash = 'abcd';
which gives
--SELECT * FROM h1
urid | devi |
-------+-----------+
1 | 6 |
2 | 3 |
4 | 3 |
following which I issue
select urid from h1 order by v2 asc limit 1;
which yields urid = 2, the result I am after. Whilst this works, I would like to know if there is a better/simpler way of doing this.
You're so close! You have all of the components you need, you just have to put them together into a single query.
Consider:
SELECT urid
, (abs(dx - :tx) + abs(dy - :tx) + abs(dz - :tx)) AS devi
FROM visits
WHERE hash=:hashval AND devi < :nearby
ORDER BY devi
LIMIT 1
Line by line, first you list the rows and computed values you want (:tx is a placeholder; in your code you want to prepare a statement and then bind values to the placeholders before executing the statement) from the visit table.
Then in the WHERE clause you restrict what rows get returned to those matching the particular hash (That column should have an index for best results... CREATE INDEX visits_idx_hash ON visits(hash) for example), and that have a devi that is less than the value of the :nearby placeholder. (I think devi < :nearby is clearer than :nearby >= devi).
Then you say that you want those results sorted in increasing order according to devi, and LIMIT the returned results to a single row because you don't care about any others (If there are no rows that meet the WHERE constraints, nothing is returned).

SQLite UPDATE returns empty

I'm trying to update a table column from another table with the code below.
Now the editor says '39 rows affected' and I can see something happened because some cells changed from null to empty (nothing shows).
While orhers are still null
What could be wrong here?
Why does it not update properly....
PS: I checked manually that the values are not empty in the column to check for.
UPDATE CANZ_CONC
SET EAN = (SELECT t1.EAN_nummer FROM ArtLev_CONC t1 WHERE t1.Artikelcode_leverancier = Artikelcode_leverancier)
WHERE ARTNMR IN (SELECT t1.Artikelcode_leverancier FROM Artlev_CONC t1 WHERE t1.Artikelcode_leverancier = ARTNMR);
Edit:
The tabel2 is like:
NMR | EAN | CUSTOM
-------------------------------
1 | 987 | A
2 | 654 | B
3 | 321 | C
Tabel 1 is like
NMR | EAN | CUSTOM
-------------------------------
1 | null | null
2 | null | null
5 | null | null
After the UPDATE table1 is like
NMR | EAN | CUSTOM
-------------------------------
1 | | null
2 | | null
5 | null | null
I've got this working.
I guess my data was corrupted after all.
Since it is about 330.000 rows it was not very easy to spot.
But it came to me when the loading of the data took about 10 minutes!
It used to be about 40 - 60 seconds.
So I ended up back at the drawing board for the initial csv file.
I also saw the columns had not been given a DATA type, so I altered that as well.
Thanx for the help!

sqlite, order by date/integer in joined table

I have two tables
Names
id | name
---------
5 | bill
15 | bob
10 | nancy
Entries
id | name_id | added | description
----------------------------------
2 | 5 | 20140908 | i added this
4 | 5 | 20140910 | added later on
9 | 10 | 20140908 | i also added this
1 | 15 | 20140805 | added early on
6 | 5 | 20141015 | late to the party
I'd like to order Names by the first of the numerically-lowest added values in the Entries table, and display the rows from both tables ordered by the added column overall, so the results will be something like:
names.id | names.name | entries.added | entries.description
-----------------------------------------------------------
15 | bob | 20140805 | added early on
5 | bill | 20140908 | i added this
10 | nancy | 20140908 | i also added this
I looked into joins on the first item (e.g. SQL Server: How to Join to first row) but wasn't able to get it to work.
Any tips?
Give this query a try:
SELECT Names.id, Names.name, Entries.added, Entries.description
FROM Names
INNER JOIN Entries
ON Names.id = Entries.name_id
ORDER BY Entries.added
Add DESC if you want it in reverse order i.e.: ORDER BY Entries.added DESC.
This should do it:
SELECT n.id, n.name, e.added, e.description
FROM Names n INNER JOIN
(SELECT name_id, description, Min(added) FROM Entries GROUP BY name_id, description) e
ON n.id = e.name_id
ORDER BY e.added

Resources