I'm trying make a query with HQL that will stay with the same order as given list of IDs. I know it's possible with SQL but I can't find any way to do it with HQL (and I cannot do it with native SQL because I got many joins)
Example
fingerIds = [3,1,10,4]
SELECT p FROM People p
JOIN FETCH p.fingers f
WHERE f.id IN :fingerIds
DB: PostgreSQL 10.4
Hibernate: 4.3.11.Final
Eg. Given list of IDs: [3,1,10,4]
Actual result's order: [1,3,4,10]
Expected result's order: [3,1,10,4]
You can obtain the order by adding to your query the keyword FIELD, in your example:
SELECT p FROM People p
JOIN FETCH p.fingers f
WHERE f.id IN :fingerIds
ORDER BY FIELD(f.ID,3,1,10,4)
Ofc you can replace the numbers with your variable :fingerIds
You can find more about that command here.
Returns the index (position) of str in the str1, str2, str3, ... list. Returns 0 if str is not found.
I have two tables which look like such
Organizations
Id (primary_key. big int)
Name (text)
CustomInformations
Id (primary_key. big int)
ConnectedIdentifiers (JSONB)
Info (text)
CustomInformations's ConnectedIdentifiers column contains a JSONB structure which looks like
{ 'organizations': [1,2,3] }
This means that there's an array of organizations with those ids 1, 2, 3, which are related to that particular CustomInformation
I'm trying to do a JOIN where given a CustomInformation Id will also get me all the Organizations names
I tried this after looking at some examples:
SELECT * FROM CustomInformations ci
INNER JOIN Organizations o on jsonb_array_elements(ci.ConnectedIdentifiers->'19') = o.id
WHERE
ci.id = 5
I got an error No operator matches the given name and argument type(s). You might need to add explicit type casts.
Is this the right approach? And if so what is wrong with my syntax?
Thanks
You cannot use jsonb_array_elements() in this way because the function returns set of rows. It should be placed in a lateral join instead. Use jsonb_array_elements_text() to get array elements as text and cast these elements to bigint:
select ci.*, o.*
from custominfo ci
-- lateral join
cross join jsonb_array_elements_text(ci.connectedidentifiers->'organizations') ar(elem)
join organizations o
on elem::bigint = o.id
where ci.id = 5
I have a 2 tables FIRST
id,rl_no,adm_date,fees
1,123456,14-11-10,100
2,987654,10-11-12,30
3,4343,14-11-17,20
and SECOND
id,rollno,fare,type
1,123456,20,bs
5,634452,1000,bs
3,123456,900,bs
4,123456,700,bs
My requirement is twofold,
1, i first need to get all columns from both tables with common rl_no. So i used:
SELECT a.ID,a.rl_no,a.adm_date,a.fees,b.rollno,b.fare,b.type FROM FIRST a
INNER JOIN
SECOND b ON a.rl_no = b.rollno
The output is like this:
id,rl_no,adm_date,fees,rollno,fare,type
1,123456,14-11-10,100,123456,20,bs
1,123456,10-11-12,100,123456,900,bs
1,123456,14-11-17,100,123456,700,bs
2,Next i wanted to get the sum(fare) of those rollno that were common between the 2 tables and also whose fare >= fees from FIRST table group by rollno and id.
My query is:
SELECT x.ID,x.rl_no,,x.adm_date,x.fees,x.rollno,x.type,sum(x.fare) as "fare" from (SELECT a.ID,a.rl_no,a.adm_date,a.fees,b.rollno,b.fare,b.type FROM FIRST a
INNER JOIN
SECOND b ON a.rl_no = b.rollno) x, FIRST y
WHERE x.rollno = y.rl_no AND x.fare >= y.fees AND x.type IS NOT NULL GROUP BY x.rollno,x.ID ;
But this is throwing in exceptions.
ORA-00979: not a GROUP BY expression
00979. 00000 - "not a GROUP BY expression"
The expected output will be like this:
id,rollno,adm_date,fare,type
1,123456,14-11-10,1620,bs
So could someone care to show an oracle newbie what i'm doing wrong here?
It looks like there's a couple different problems here;
Firstly, you're trying to group by an x.ID column which doesn't exist; it looks like you'll want to add ID to the selected columns in your sub-query.
Secondly, when aggregating with GROUP BY, all selected columns need to be either listed in the GROUP BY statement or aggregated. If you're grouping by rollno and ID, what do you want to have happen to all the extra values for adm_date, fees, and type? Are those always going to be the same for each distinct rollno and ID pair?
If so, simply add them to the GROUP BY statement, ie,
GROUP BY adm_date, fees, type, rollno, ID
If not, you'll need to work out exactly how you want to select which one to be output; If you've got output like your example (adding in an ID column here)
ID,adm_date,fees,rollno,fare,type
1,14-11-10,100,123456,20,bs
1,10-11-12,100,123456,900,bs
1,14-11-17,100,123456,700,bs
Call that result set 'a'. If I run;
SELECT a.ID, a.rollno, SUM(a.fare) as total_fare
FROM a
GROUP BY a.ID, a.rollno
Then the result will be a single row;
ID,rollno,total_fare
1,123456,1620
So, if you also select the adm_date, fees, and type columns, oracle has no idea what you mean to do with them. You're not using them for grouping, and you're not telling oracle how you want to pick which one to use.
You could do something like
SELECT a.ID,
FIRST(a.adm_date) as first_adm_date,
FIRST(a.fees) as first_fees,
a.rollno,
SUM(a.fare) as total_fare,
FIRST(a.type) as first_type
FROM a
GROUP BY a.ID, a.rollno
Which would give the result;
ID,first_adm_date,first_fees,rollno,total_fare,first_type
1,14-11-10,100,123456,1620,bs
I'm not sure if that's what you mean to do though.
I'm trying to join a table that might have multiple entries for the given id and aggregate the rows corresponding to this id in an array. This looks as follows in the SQL query:
SELECT * from data
LEFT JOIN (select id, array_agg(row(foo, bar)) AS foo_bar_data from foo_bar_table group by id) AS temp using(id)
This works as intended, but I'm having trouble reading out the result in JDBC.
ResultSet rs = st.executeQuery(...)
Array a = rs.getArray("foo_bar_data")
// Now I want to iterate over the array, reading the values foo and bar of each item.
My efforts so far always ended in a Method org.postgresql.jdbc4.Jdbc4Array.getArrayImpl(long,int,Map) is not yet implemented. exception. How can I iterate over a, retrieving the values foo and bar?
Edit: I should possibly also mention, that foo and bar don't have the same type.
Postgres JDBC driver does not support anything except basic types (numbers, date/timestamp, string) as JDBC array. You can call array_agg twice and get two arrays on each row:
try (Connection db = DriverManager.getConnection("jdbc:postgresql://localhost:5432/postgres", "postgres", "postgres");
ResultSet rs = db.createStatement().executeQuery("select array_agg(i), array_agg(s) from (select 1 i, 'a' s union select 2 i, 'b' s) t")) {
rs.next();
System.out.println(Arrays.toString((Object[]) rs.getArray(1).getArray()));
System.out.println(Arrays.toString((Object[]) rs.getArray(2).getArray()));
}
SELECT (a+b) as c FROM my_table ORDER BY c ASC;
How can I order by two columns sum in Mongo?
You can't do it easy without an extra action.
To sort on any computed value you need to store it in a document first or in other worlds you need to create extra field 'c', and store a + b in it with each update/insert and only then sort on 'c' as usual.
You can achieve like this query:
db.mycol.aggregate(
[{$match:{tag:"xxx"}},
{$project:{tag:1, count_a:1, count_b:1, factor:{$add: ["$count_a", "$count_b"]}}},
{$sort:{factor:-1}}]
)