I've got following query
SELECT ID FROM MARMELADES mrm
where not exists
(SELECT 1 FROM TOYS toys
WHERE mrm.ID = toys.ID
AND mrm.INGREDIENT = toys.INGREDIENT
AND mrm.BOX_TYPE = 2)
AND mrm.BOX_TYPE = 2
It returns almost 400+ results of id, for example [12, 33, 45, ... , 3405]
Now, i want to remove all ids that are from that list everywhere from my database. this is not only MARMELADES and TOYS. Also, i have for example 35+ tables where i can have this id).
I would be happy if this query could extract in some functions like ALL_UNNEEDED_IDS so i can use it like this:
DELETE FROM ANOTHER_TABLE_1 WHERE ID IN ( ALL_UNNEEDED_IDS )
DELETE FROM ANOTHER_TABLE_2 WHERE ID IN ( ALL_UNNEEDED_IDS )
DELETE FROM ANOTHER_TABLE_3 WHERE ID IN ( ALL_UNNEEDED_IDS )
DELETE FROM ANOTHER_TABLE_4 WHERE ID IN ( ALL_UNNEEDED_IDS )
...
DELETE FROM ANOTHER_TABLE_35 WHERE ID IN ( ALL_UNNEEDED_IDS )
It is possible to do it in oracle to reuse such results?
Use the first query within your subsequent queries. IE:
DELETE FROM ANOTHER_TABLE_1 WHERE ID IN (
SELECT ID FROM MARMELADES mrm
where not exists
(SELECT 1 FROM TOYS toys
WHERE mrm.ID = toys.ID
AND mrm.INGREDIENT = toys.INGREDIENT
AND mrm.BOX_TYPE = 2)
AND mrm.BOX_TYPE = 2
);
When you get to the toys and marmelades tables, you'll need a temporary holder table as #Gordon suggests.
Related
I am working with nodejs and postgresql. My postgresql relation has 3 columns:
id
lesson_id
tag_id.
A lesson could belong to 1 or multiple tags.
I am trying to select all the lesson whose belongs to the requested tags.
For example
tags requested are id 10 and 2, the query should response with lesson id = 3
tags requested are id 1 and 17, the query should response with lesson id = 6
tag requested is 3, the query should response with lessons id 1, 2, 4
I have tried some sql queries like this one:
const selectLessonByTag = await pgClient.query(
`SELECT DISTINCT ON (lesson_id)
lesson_id FROM "lesson_has_tag"
WHERE tag_id = $1 AND tag_id = $2
GROUP BY lesson_id
ORDER BY lesson_id`,
[2,10]);
but it's not the expected answer.
You can use not exists like so:
select distinct lesson_id
from lesson_tags as lt1
where not exists (
select *
from (values (10), (2)) as required_tags(tag_id)
where not exists (
select *
from lesson_tags as lt2
where lt2.lesson_id = lt1.lesson_id and lt2.tag_id = required_tags.tag_id
)
)
It is difficult to digest so little explanation:
There is a table valued constructor called required_tags containing values 10 and 2
The inner query tests if 10 or 2 do not exist for a lesson from the outer query
If the inner query does not produce a match the outer row selected
DB<>Fiddle
I am writing a HIVE query to pull about 2,000 unique keys from a table.
I keep getting this error - java.lang.StackOverflowError
My query is basic but looks like this:
SELECT * FROM table WHERE (Id = 1 or Id = 2 or Id = 3 Id = 4)
my WHERE clause goes all the way up to 2000 unique id's and I receive the error above. Does anyone know of a more efficient way to do this or get this query to work?
Thanks!
You may use the SPLIT and EXPLODE to convert the comma separated string to rows and then use IN or EXISTS.
using IN
SELECT * FROM yourtable t WHERE
t.ID IN
(
SELECT
explode(split('1,2,3,4,5,6,1998,1999,2000',',')) as id
) ;
Using EXISTS
SELECT * FROM yourtable t WHERE
EXISTS
(
SELECT 1 FROM (
SELECT
explode(split('1,2,3,4,5,6,1998,1999,2000',',')) as id
) s
WHERE s.id = t.id
);
Make use of the Between clause instead of specifying all unique ids:
SELECT ID FROM table WHERE ID BETWEEN 1 AND 2000 GROUP BY ID;
i you can create a table for these IDs and after use the condition of exist in the new table to get only your specific IDs
I've a scenario where I need to write sql query base on result of other query.
Consider the table data:
id attribute
1 a
1 b
2 a
3 a
3 b
3 c
I want to write query to select id base on attribute set.
I mean first I need to check attribute of id 1 using this query:
select attribute from table where id = 1
then base on this result I need to select subset of attribute. like in our case 1(a,b) is the subset of 3(a,b,c). My query should return 3 on that case.
And if I want to check base on 2(a) which is the subset of 1(a,b) and 3(a,b,c), it should return 1 and 3.
I hope, it's understandable. :)
You could use this query.
Logic is simple: If there isn't any item in A and isn't in B --> A is subset of B.
DECLARE #SampleData AS TABLE
(
Id int, attribute varchar(5)
)
INSERT INTO #SampleData
VALUES (1,'a'), (1,'b'),
(2,'a'),
(3,'a'),(3,'b'),(3,'c')
DECLARE #FilterId int = 1
;WITH temp AS
(
SELECT DISTINCT sd.Id FROM #SampleData sd
)
SELECT * FROM temp t
WHERE t.Id <> #FilterId
AND NOT EXISTS (
SELECT sd2.attribute FROM #SampleData sd2
WHERE sd2.Id = #FilterId
AND NOT EXISTS (SELECT * FROM #SampleData sd WHERE sd.Id = t.Id AND sd.attribute = sd2.attribute)
)
Demo link: Rextester
I would compose a query for that in three steps: first I'd get the attributes of the desired id, and this is the query you wrote
select attribute from table where id = 1
Then I would get the number of attributes for the required id
select count(distinct attribute) from table where id = 1
Finally I would use the above results as filters
select id
from table
where id <> 1 and
attribute in (
select attribute from table where id = 1 /* Step 1 */
)
group by id
having count(distinct attribute) = (
select count(distinct attribute) from table where id = 1 /* Step 2 */
)
This will get you all the id's that have a number of attributes among those of the initially provided id equal to the number the initial id has.
i have this sample data :-
===============
pageid||SiteID
===============
61 || 1
62 || 1
63 || 1
62 || 2
and
this table refrence to other table for pages , pageid unique in other
table
i need to delete data from this table and the referencing table ....but if the record repeat with other site id i must not delete it , when i select with site id all pageid will delete ( i can delete all pageid but 62 i want keept it in page table )
Use NOT EXISTS clause to prevent delete of pageid used in different siteID
Try this:
DELETE FROM yourtable
WHERE NOT EXISTS(
SELECT 'OTHERSITE'
FROM yourtable T2
WHERE T2.pageid = yourtable.pageid
AND T2.siteID <> yourtable.siteID)
DELETE FROM #Page_Site
WHERE siteID=#siteID
AND pageID not
in(
SELECT pageID
FROM #Page_Site p2
WHERE p2.siteID!=#siteID
);
I'm not certain how you use your query, so I formatted it as a parametered query. Otherwise, you simply have to replace both instances of #siteID with a any given value.
I like the way that SQL Server allows window functions with delete and update. So, it is also possible to use these functions for this purpose:
with todelete as (
select s.*, min(siteId) over (partition by pageid) as mins,
max(siteId) over (partition by pageid) as maxs
from sample s
)
delete from todelete
where mins = maxs;
You'll need to do that in 2 queries. First delete all the linking id's, secondly delete the pages itself
delete from pageSiteLinks
where pageid in (
select pageid
from pageSiteLinks
group by pageid
having count(SiteID) = 1
);
delete from pages
where pageid not in (
select pageid
from pageSiteLinks
);
I have an Access table of the form (I'm simplifying it a bit)
ID AutoNumber Primary Key
SchemeName Text (50)
SchemeNumber Text (15)
This contains some data eg...
ID SchemeName SchemeNumber
--------------------------------------------------------------------
714 Malcolm ABC123
80 Malcolm ABC123
96 Malcolms Scheme ABC123
101 Malcolms Scheme ABC123
98 Malcolms Scheme DEF888
654 Another Scheme BAR876
543 Whatever Scheme KJL111
etc...
Now. I want to remove duplicate names under the same SchemeNumber. But I want to leave the record which has the longest SchemeName for that scheme number. If there are duplicate records with the same longest length then I just want to leave only one, say, the lowest ID (but any one will do really). From the above example I would want to delete IDs 714, 80 and 101 (to leave only 96).
I thought this would be relatively easy to achieve but it's turning into a bit of a nightmare! Thanks for any suggestions. I know I could loop it programatically but I'd rather have a single DELETE query.
See if this query returns the rows you want to keep:
SELECT r.SchemeNumber, r.SchemeName, Min(r.ID) AS MinOfID
FROM
(SELECT
SchemeNumber,
SchemeName,
Len(SchemeName) AS name_length,
ID
FROM tblSchemes
) AS r
INNER JOIN
(SELECT
SchemeNumber,
Max(Len(SchemeName)) AS name_length
FROM tblSchemes
GROUP BY SchemeNumber
) AS w
ON
(r.SchemeNumber = w.SchemeNumber)
AND (r.name_length = w.name_length)
GROUP BY r.SchemeNumber, r.SchemeName
ORDER BY r.SchemeName;
If so, save it as qrySchemes2Keep. Then create a DELETE query to discard rows from tblSchemes whose ID value is not found in qrySchemes2Keep.
DELETE
FROM tblSchemes AS s
WHERE Not Exists (SELECT * FROM qrySchemes2Keep WHERE MinOfID = s.ID);
Just beware, if you later use Access' query designer to make changes to that DELETE query, it may "helpfully" convert the SQL to something like this:
DELETE s.*, Exists (SELECT * FROM qrySchemes2Keep WHERE MinOfID = s.ID)
FROM tblSchemes AS s
WHERE (((Exists (SELECT * FROM qrySchemes2Keep WHERE MinOfID = s.ID))=False));
DELETE FROM Table t1
WHERE EXISTS (SELECT 1 from Table t2
WHERE t1.SchemeNumber = t2.SchemeNumber
AND Length(t2.SchemeName) > Length(t1.SchemeName)
)
Depend on your RDBMS you may use function different from Length (Oracle - length, mysql - length, sql server - LEN)
delete ShortScheme
from Scheme ShortScheme
join Scheme LongScheme
on ShortScheme.SchemeNumber = LongScheme.SchemeNumber
and (len(ShortScheme.SchemeName) < len(LongScheme.SchemeName) or (len(ShortScheme.SchemeName) = len(LongScheme.SchemeName) and ShortScheme.ID > LongScheme.ID))
(SQL Server flavored)
Now updated to include the specified tie resolution. Although, you may get better performance doing it in two queries: first deleting the schemes with shorter names as in my original query and then going back and deleting the higher ID where there was a tie in name length.
I'd do this in multiple steps. Large delete operations done in a single step make me too nervous -- what if you make a mistake? There's no sql 'undo' statement.
-- Setup the data
DROP Table foo;
DROP Table bar;
DROP Table bat;
DROP Table baz;
CREATE TABLE foo (
id int(11) NOT NULL,
SchemeName varchar(50),
SchemeNumber varchar(15),
PRIMARY KEY (id)
);
insert into foo values (714, 'Malcolm', 'ABC123' );
insert into foo values (80, 'Malcolm', 'ABC123' );
insert into foo values (96, 'Malcolms Scheme', 'ABC123' );
insert into foo values (101, 'Malcolms Scheme', 'ABC123' );
insert into foo values (98, 'Malcolms Scheme', 'DEF888' );
insert into foo values (654, 'Another Scheme ', 'BAR876' );
insert into foo values (543, 'Whatever Scheme ', 'KJL111' );
-- Find all the records that have dups, find the longest one
create table bar as
select max(length(SchemeName)) as max_length, SchemeNumber
from foo
group by SchemeNumber
having count(*) > 1;
-- Find the one we want to keep
create table bat as
select min(a.id) as id, a.SchemeNumber
from foo a join bar b on a.SchemeNumber = b.SchemeNumber
and length(a.SchemeName) = b.max_length
group by SchemeNumber;
-- Select into this table all the rows to delete
create table baz as
select a.id from foo a join bat b where a.SchemeNumber = b.SchemeNumber
and a.id != b.id;
This will give you a new table with only records for rows that you want to remove.
Now check these out and make sure that they contain only the rows you want deleted. This way you can make sure that when you do the delete, you know exactly what to expect. It should also be pretty fast.
Then when you're ready, use this command to delete the rows using this command.
delete from foo where id in (select id from baz);
This seems like more work because of the different tables, but it's safer probably just as fast as the other ways. Plus you can stop at any step and make sure the data is what you want before you do any actual deletes.
If your platform supports ranking functions and common table expressions:
with cte as (
select row_number()
over (partition by SchemeNumber order by len(SchemeName) desc) as rn
from Table)
delete from cte where rn > 1;
try this:
Select * From Table t
Where Len(SchemeName) <
(Select Max(Len(Schemename))
From Table
Where SchemeNumber = t.SchemeNumber )
And Id >
(Select Min (Id)
From Table
Where SchemeNumber = t.SchemeNumber
And SchemeName = t.SchemeName)
or this:,...
Select * From Table t
Where Id >
(Select Min(Id) From Table
Where SchemeNumber = t.SchemeNumber
And Len(SchemeName) <
(Select Max(Len(Schemename))
From Table
Where SchemeNumber = t.SchemeNumber))
if either of these selects the records that should be deleted, just change it to a delete
Delete
From Table t
Where Len(SchemeName) <
(Select Max(Len(Schemename))
From Table
Where SchemeNumber = t.SchemeNumber )
And Id >
(Select Min (Id)
From Table
Where SchemeNumber = t.SchemeNumber
And SchemeName = t.SchemeName)
or using the second construction:
Delete From Table t Where Id >
(Select Min(Id) From Table
Where SchemeNumber = t.SchemeNumber
And Len(SchemeName) <
(Select Max(Len(Schemename))
From Table
Where SchemeNumber = t.SchemeNumber))