I use sql below to join DRAT & DRAP.
SELECT * INTO CORRESPONDING FIELDS OF WA_DOC_LOG
FROM DRAP
INNER JOIN DRAT ON DRAP~DOKNR = DRAT~DOKNR
AND DRAP~DOKAR = DRAT~DOKAR
WHERE DRAP~DOKNR IN S_DOKNR
AND DRAP~DOKAR IN S_DOKAR
AND DRAP~DOKST IN S_DOKST
AND DRAP~DATUM IN S_DATUM.
But when I display, I just want to display the record with highest version number (DRAP~DOKVR). What is the possible ways to eliminate the records with lower version?
I would probably off-load this to the application server:
SORT documents BY dokar doknr dokvr DESCENDING. " careful with doktl!
DELETE ADJACENT DUPLICATES FROM documents COMPARING dokar doknr.
Using SQL to achieve this might be possible, but I'd be very careful since this might turn out to be rather expensive unless done right.
Try this SELECT statement:
SELECT *
INTO CORRESPONDING FIELDS OF TABLE WA_DOC_LOG
FROM DRAP AS d
INNER JOIN DRAT AS t
ON d~DOKNR = t~DOKNR
AND d~DOKAR = t~DOKAR
WHERE d~dokvr = ( SELECT max( dokvr ) FROM drap ).
Although, it is not very efficient, but functional yet. You should consider performance on your concrete system yourself.
Related
I have the following SQL-code in my (SAP IdM) Application:
Select mcmskeyvalue as MKV,v1.searchvalue as STARTDATE, v2.avalue as Running_Changes_flag
from idmv_entry_simple
inner join idmv_value_basic_active v1 on mskey = mcmskey and attrname = 'Start_of_company_change'
and mcentrytype = 'MX_PERSON' and to_date(v1.searchvalue,'YYYY-MM-DD')<= sysdate+3
left join idmv_value_basic v2 on v2.mskey = mcmskey and v2.attrname = 'Running_Changes_flag'
where mcmskey not in (Select mskey from idmv_value_basic_active where attrname = 'Company_change_running_flag')
I already found the solution for the ORA-01841 problem, as it could either be a solution similar to MSSQLs try_to_date as mentioned here: How to handle to_date exceptions in a SELECT statment to ignore those rows?
or a solution where I change the code to something like this, to work soly on strings:
Select mcmskeyvalue as MKV,v1.searchvalue as STARTDATE, v2.avalue as Running_Changes_flag
from idmv_entry_simple
inner join idmv_value_basic_active v1 on mskey = mcmskey and attrname = 'Start_of_company_change'
and mcentrytype = 'MX_PERSON' and v1.searchvalue<= to_char(sysdate+3,'YYYY-MM-DD')
left join idmv_value_basic v2 on v2.mskey = mcmskey and v2.attrname = 'Running_Changes_flag'
where mcmskey not in (Select mskey from idmv_value_basic_active where attrname = 'Company_change_running_flag')
So for the actually problem I have a solution.
But now I came into discussion with my customers and teammates why the error happens at all.
Basically for all entries of idmv_value_basic_activ that comply to the requirement of "attrname = 'Start_of_company_change'" we can be sure that those are dates. In addition, if we execute the query to check all values that would be delivered, all are in a valid format.
I learned in university that the DB-Engine could decide in which order it will run individual segments of a query. So for me the most logical explanation would be that, on the development environment (where we face the problem), the section " to_date(v1.searchvalue,'YYYY-MM-DD')<= sysdate+3” is executed before the section “attrname = 'Start_of_company_change'”
Whereas on the productive environment, where everything works like a charm, the segments are executed in the order that is descripted by the SQL Statement.
Now my Question is:
First: do I remember that right, since the teacher said that only once and at that time I could not really make sense out of it
And Second: Is this assumption of mine correct or is there another reason for the problem?
Borderinformation:
The Tool uses a kind of shifted data structure which is why there can be quite a few different types in the actual “Searchvalue” column of the idmv_value_basic_activ view. The datatype on the database layer is always a varchar one.
"the DB-Engine could decide in which order it will run individual segments of a query"
This is correct. A SQL query is just a description of the data you want and where it's stored. Oracle will calculate an execution plan to retrieve that data as best it can. That plan will vary based on any number of factors, like the number of actual rows in the table and the presence of indexes, so it will vary from environment to environment.
So it sounds like you have an invalid date somewhere in your table, so to_date raises an exception. You can use validate_conversion to find it.
Im building a code that learns tic tac toe, by saving info in a database.
I have two tables, Games(ID,Winner) and Turns(ID,Turn,GameID,Place,Shape).
I want to find parent by multiple child infos.
For Example:
SELECT GameID FROM Turns WHERE
GameID IN (WHEN Turn = 1 THEN Place = 1) AND GameID IN (WHEN Turn = 2 THEN Place = 4);
Is something like this possible?
Im using ms-access.
Turm - Game turn GameID - Game ID Place - Place on matrix
1=top right, 9=bottom left Shape - X or circle
Thanks in advance
This very simple query will do the trick in a single scan, and doesn't require you to violate First Normal Form by storing multiple values in a string (shudder).
SELECT T.GameID
FROM Turns AS T
WHERE
(T.Turn = 1 AND T.Place = 1)
OR (T.Turn = 2 AND T.Place = 4)
GROUP BY T.GameID
HAVING Count(*) = 2;
There is no need to join to determine this information, as is suggested by other answers.
Please use proper database design principles in your database, and don't violate First Normal Form by storing multiple values together in a single string!
The general solution to your problem can be accomplished by using a sub-query that contains a self-join between two instances of the Turns table:
SELECT * FROM Games
WHERE GameID IN
(
SELECT Turns1.GameID
FROM Turns AS Turns1
INNER JOIN Turns AS Turns2
ON Turns1.GameID = Turns2.GameID
WHERE (
(Turns1.Turn=1 AND Turns1.Place = 1)
AND
(Turns2.Turn=2 AND Turns2.Place = 4))
);
The Self Join between Turns (aliased Turns1 and Turns2) is key, because if you just try to apply both sets of conditions at once like this:
WHERE (
(Turns.Turn=1 AND Turns.Place = 1)
AND
(Turns.Turn=2 AND Turns.Place = 4))
you will never get any rows back. This is because in your table there is no way for an individual row to satisfy both conditions at the same time.
My experience using Access is that to do a complex query like this you have to use the SQL View and type the query in on your own, rather than use the Query Designer. It may be possible to do in the Designer, but it's always been far easier for me to write the code myself.
select GameID from Games g where exists (select * from turns t where
t.gameid = g.gameId and ((turn =1 and place = 1) or (turn =2 and place =5)))
This will select all the games that have atleast one turn with the coresponding criteria.
More info on exist:
http://www.techonthenet.com/sql/exists.php
I bypassed this problem by adding a column which holds the turns as a string example : "154728" and i search for it instead. I think this solution is also less demanding on the database
I have this query using PostgreSQL 9.1 (9.2 as soon as our hosting platform upgrades):
SELECT
media_files.album,
media_files.artist,
ARRAY_AGG (media_files. ID) AS media_file_ids
FROM
media_files
INNER JOIN playlist_media_files ON media_files.id = playlist_media_files.media_file_id
WHERE
playlist_media_files.playlist_id = 1
GROUP BY
media_files.album,
media_files.artist
ORDER BY
media_files.album ASC
and it's working fine, the goal was to extract album/artist combinations and in the result set have an array of media files ids for that particular combo.
The problem is that I have another column in media files, which is artwork.
artwork is unique for each media file (even in the same album) but in the result set I need to return just the first of the set.
So, for an album that has 10 media files, I also have 10 corresponding artworks, but I would like just to return the first (or a random picked one for that collection).
Is that possible to do with only SQL/Window Functions (first_value over..)?
Yes, it's possible. First, let's tweak your query by adding alias and explicit column qualifiers so it's clear what comes from where - assuming I've guessed correctly, since I can't be sure without table definitions:
SELECT
mf.album,
mf.artist,
ARRAY_AGG (mf.id) AS media_file_ids
FROM
"media_files" mf
INNER JOIN "playlist_media_files" pmf ON mf.id = pmf.media_file_id
WHERE
pmf.playlist_id = 1
GROUP BY
mf.album,
mf.artist
ORDER BY
mf.album ASC
Now you can either use a subquery in the SELECT list or maybe use DISTINCT ON, though it looks like any solution based on DISTINCT ON will be so convoluted as not to be worth it.
What you really want is something like an pick_arbitrary_value_agg aggregate that just picks the first value it sees and throws the rest away. There is no such aggregate and it isn't really worth implementing it for the job. You could use min(artwork) or max(artwork) and you may find that this actually performs better than the later solutions.
To use a subquery, leave the ORDER BY as it is and add the following as an extra column in your SELECT list:
(SELECT mf2.artwork
FROM media_files mf2
WHERE mf2.artist = mf.artist
AND mf2.album = mf.album
LIMIT 1) AS picked_artwork
You can at a performance cost randomize the selected artwork by adding ORDER BY random() before the LIMIT 1 above.
Alternately, here's a quick and dirty way to implement selection of a random row in-line:
(array_agg(artwork))[width_bucket(random(),0,1,count(artwork)::integer)]
Since there's no sample data I can't test these modifications. Let me know if there's an issue.
"First" pick
Wouldn't it be simpler / cheaper to just use min():
SELECT m.album
,m.artist
,array_agg(m.id) AS media_file_ids
,min(m.artwork) AS artwork
FROM playlist_media_files p
JOIN media_files m ON m.id = p.media_file_id
WHERE p.playlist_id = 1
GROUP BY m.album, m.artist
ORDER BY m.album, m.artist;
Abitrary / random pick
If you are looking for a random selection, #Craig already provided a solution with truly random picks.
You could also use a CTE to avoid additional scans on the (possibly big) base table and then run two separate (cheap) subqueries on the small result set.
For arbitrary selection - not truly random, the result will depend on the physical order of rows in the table and implementation-specifics:
WITH x AS (
SELECT m.album, m.artist, m.id, m.artwork
FROM playlist_media_files p
JOIN media_files m ON m.id = p.media_file_id
)
SELECT a.album, a.artist, a.media_file_ids, b.artwork
FROM (
SELECT album, artist, array_agg(id) AS media_file_ids
FROM x
) a
JOIN (
SELECT DISTINCT ON (1,2) album, artist, artwork
FROM x
) b USING (album, artist);
For truly random results, you can add an ORDER BY .. random() like this to subquery b:
JOIN (
SELECT DISTINCT ON (1, 2) album, artist, artwork
FROM x
ORDER BY 1, 2, random()
) b USING (album, artist);
I have created a database for an imaginary solicitors, my last query to complete is driving me insane. I need to work out the total a solicitor has made in their career with the company, I have time_spent and rate to multiply and special rate to add. (special rate is a one off charge for corporate contracts so not many cases have them). the best I could come up with is the code below. It does what I want but only displays the solicitors working on a case with a special rate applied to it.
I essentially want it to display the result of the query in a table even if the special rate is NULL.
I have ordered the table to show the highest amount first so i can use ROWNUM to only show the top 10% earners.
CREATE VIEW rich_solicitors AS
SELECT notes.time_spent * rate.rate_amnt + special_rate.s_rate_amnt AS solicitor_made,
notes.case_id
FROM notes,
rate,
solicitor_rate,
solicitor,
case,
contract,
special_rate
WHERE notes.solicitor_id = solicitor.solicitor_id
AND solicitor.solicitor_id = solicitor_rate.solicitor_id
AND solicitor_rate.rate_id = rate.rate_id
AND notes.case_id = case.case_id
AND case.contract_id = contract.contract_id
AND contract.contract_id = special_rate.contract_id
ORDER BY -solicitor_made;
Query:
SELECT *
FROM rich_solicitors
WHERE ROWNUM <= (SELECT COUNT(*)/10
FROM rich_solicitors)
I'm suspicious of your use of ROWNUM in your example query...
Oracle9i+ supports analytic functions, like ROW_NUMBER and NTILE, to make queries like your example easier. Analytics are also ANSI, so the syntax is consistent when implemented (IE: Not on MySQL or SQLite). I re-wrote your query as:
SELECT x.*
FROM (SELECT n.time_spent * r.rate_amnt + COALESCE(spr.s_rate_amnt, 0) AS solicitor_made,
n.case_id,
NTILE(10) OVER (ORDER BY solicitor_made) AS rank
FROM NOTES n
JOIN SOLICITOR s ON s.solicitor_id = n.solicitor_id
JOIN SOLICITOR_RATE sr ON sr.solicitor_id = s.solicitor_id
JOIN RATE r ON r.rate_id = sr.rate_id
JOIN CASE c ON c.case_id = n.case_id
JOIN CONTRACT cntrct ON cntrct.contract_id = c.contract_id
LEFT JOIN SPECIAL_RATE spr ON spr.contract_id = cntrct.contract_id) x
WHERE x.rank = 1
If you're new to SQL, I recommend using ANSI-92 syntax. Your example uses ANSI-89, which doesn't support OUTER JOINs and is considered deprecated. I used a LEFT OUTER JOIN against the SPECIAL_RATE table because not all jobs are likely to have a special rate attached to them.
It's also not recommended to include an ORDER BY in views, because views encapsulate the query -- no one will know what the default ordering is, and will likely include their own (waste of resources potentially).
you need to left join in the special rate.
If I recall the oracle syntax is like:
AND contract.contract_id = special_rate.contract_id (+)
but now special_rate.* can be null so:
+ special_rate.s_rate_amnt
will need to be:
+ coalesce(special_rate.s_rate_amnt,0)
We have a database that stores vehicle's gps position, date, time, vehicle identification, lat, long, speed, etc., every minute.
The following select pulls each vehicle position and info, but the problem is that returns the first record, and I need the last record (current position), based on date (datagps.Fecha) and time (datagps.Hora). This is the select:
SELECT configgps.Fichagps,
datacar.Ficha,
groups.Nombre,
datagps.Hora,
datagps.Fecha,
datagps.Velocidad,
datagps.Status,
datagps.Calleune,
datagps.Calletowo,
datagps.Temp,
datagps.Longitud,
datagps.Latitud,
datagps.Evento,
datagps.Direccion,
datagps.Provincia
FROM asigvehiculos
INNER JOIN datacar ON (asigvehiculos.Iddatacar = datacar.Id)
INNER JOIN configgps ON (datacar.Configgps = configgps.Id)
INNER JOIN clientdata ON (asigvehiculos.Idgroup = clientdata.group)
INNER JOIN groups ON (clientdata.group = groups.Id)
INNER JOIN datagps ON (configgps.Fichagps = datagps.Fichagps)
Group by Fichagps;
I need same result I'm getting, but instead of the older record I need the most recent
(LAST datagps.Fecha / datagps.Hora).
How can I accomplish this?
Add ORDER BY datagps.Fecha DESC, datagps.Hora DESC LIMIT 1 to your query.
I'm not sure why you are having any problems with this as Lex's answers seem good.
I would start putting ORDER BY's in your query so it puts them in an order, when it's showing the record you want as the first one in the list, then add the LIMIT.
If you want the most recent, then the following should be good enough:
ORDER BY datagps.Fecha DESC, datagps.Hora DESC
If you simply want the record that was added to the database most recently (irregardless of the date/time fields), then you could (assuming you have an auto-incremental primary key in the datagps table (I assume it's called dataID for this example)):
ORDER BY datagps.dataID DESC
If these aren't showing the data you want - then there is something missing from your example (maybe data-types aren't DATETIME fields? - if not - then maybe a CONVERT to change them from their current type before ORDERing BY would be a good idea)
EDIT:
I've seen the screenshot and I'm confused as to what the issue is still. That appears to be showing everything in order. Are you implying that there are many more than 5 records? How many are you expecting?
Do you mean: for each record returned, you want the one row from the table datagps with the latest date and time attached to the result? If so, how about this:
# To show how the query will be executed
# comment to return actual results
EXPLAIN
SELECT
configgps.Fichagps, datacar.Ficha, groups.Nombre, datagps.Hora, datagps.Fecha,
datagps.Velocidad, datagps.Status, datagps.Calleune, datagps.Calletowo,
datagps.Temp, datagps.Longitud, datagps.Latitud, datagps.Evento,
datagps.Direccion, datagps.Provincia
FROM asigvehiculos
INNER JOIN datacar ON (asigvehiculos.Iddatacar = datacar.Id)
INNER JOIN configgps ON (datacar.Configgps = configgps.Id)
INNER JOIN clientdata ON (asigvehiculos.Idgroup = clientdata.group)
INNER JOIN groups ON (clientdata.group = groups.Id)
INNER JOIN datagps ON (configgps.Fichagps = datagps.Fichagps)
########### Add this section
LEFT JOIN datagps b ON (
configgps.Fichagps = b.Fichagps
# wrong condition
#AND datagps.Hora < b.Hora
#AND datagps.Fecha < b.Fecha)
# might prevent indexes to be used
AND (datagps.Fecha < b.Fecha OR (datagps.Fecha = b.Fecha AND datagps.Hora < b.Hora))
WHERE b.Fichagps IS NULL
###########
Group by configgps.Fichagps;
Similar question here only that that one uses outer joins.
Edit (again):
The conditions are wrong so corrected it. Can you show us the output of the above EXPLAIN query so we can pinpoint where the bottle neck is?
As hurikhan77 said, it will be better if you could convert both of the the columns into a single datetime field - though I'm guessing this would not be possible for your case (since your database is already being used?)
Though if you can convert it, the condition (on the join) would become:
AND datagps.FechaHora < b.FechaHora
After that, add an index for datagps.FechaHora and the query would be fast(er).
What you probably want is getting the maximum of (Fecha,Hora) per grouped dataset? This is a little complicated to accomplish with your column types. You should combine Fecha and Hora into one column of type DATETIME. Then it's easy to just SELECT MAX(FechaHora) ... GROUP BY Fichagps.
It could have helped if you posted your table structure to understand the problem.