I am unable to select the rows where TestId is max for respective student, I wrote the code as follows which does not get the required output. my code is as follows,
Criteria c = sessionFactory.getCurrentSession().createCriteria(student.class).setProjection(Projections.projectionList().add(Projections.property("answer"),"answer"));
c.add(Restrictions.eq("surveyId",send_Survey));
//c.add(Restrictions.eq("testId", "1" ));
//c.setProjection(Projection.max("testId"));
c.addOrder(Order.desc("testId"));
c.add(Restrictions.eq("questionid",FinalQuestionsOne));
List<String> age=c.list();
My table structure is as follows,
I need the following output. select the answer column for max TestId's. How can I get the output using criteria query
So I think what you're trying to get can be achievedd by the following sql:
SELECT TestId, MAX(answer) WHERE questionId = 1 GROUP BY TestId;
You should be able to achieve this with the following Hibernate:
sessionFactory.getCurrentSession().createCriteria(student.class).setProjection(Projections.projectionList()
.add(Projections.property("TestId"), "TestId")
.add(Projections.groupProperty("TestId"))
.add(Projections.max("answer")));
Related
The table in question has ~30mio records. Using Entity Framework I write a LINQ Query like this:
dbContext.MyTable.FirstOrDefault(t => t.Col3 == "BQJCRHHNABKAKU-KBQPJGBKSA-N");
Devart DotConnect for Oracle generates this:
SELECT
Extent1.COL1,
Extent1.COL2,
Extent1.COL3
FROM MY_TABLE Extent1
WHERE (Extent1.COL3 = :p__linq__0) OR ((Extent1.COL3 IS NULL) AND (:p__linq__0 IS NULL))
FETCH FIRST 1 ROWS ONLY
The query takes about four minutes, obviously a full table scan.
However, handcrafting this SQL:
SELECT
Extent1.COL1,
Extent1.COL2,
Extent1.COL3
FROM MY_TABLE Extent1
WHERE Extent1.COL3 = :p__linq__0
FETCH FIRST 1 ROWS ONLY
returns the expected match in 200ms.
Question: Why is it so? I would expect the query optimizer to note that the right part is false if the parameter is not null, so why doesn't the first query hit the index?
Please set UseCSharpNullComparisonBehavior=false explicitly:
var config = Devart.Data.Oracle.Entity.Configuration.OracleEntityProviderConfig.Instance;
config.QueryOptions.UseCSharpNullComparisonBehavior = false;
If this doesn't help, send us a small test project with the corresponding DDL script so that we can investigate the issue.
This question has been posted several times but I am not able to get it work. I tried the approach mentioned in Update column to the COUNT of rows for specific values in another column. SQL Server. It gives me SQLException: java.sql.SQLException: ORA-01427: single-row subquery returns more than one row error not sure what I can do.
Below is my problem
UPDATE dataTable
SET ACCX = (select b.cnt
from dataTable a
join
(SELECT Account,
COUNT(1) cnt
FROM dataTable
GROUP BY Account) b
on a.Account=b.Account)
,ACCR = 15481
,ACCF = 3
WHERE ID = 1625
I only have the access & can change to the bold part since rest of the query is generated by the tool I cannot change it & I have to update ACCX column with the count of the value in column Account. Is it possible to do?
Note: - Account column is already populated with values.
You cannot follow that query because it is for sqlserver and NOT oracle. It is simpler in oracle and does not need a join to itself.
This update will set the count for id 1625 only based on number of account numbers in datatable. See demo here;
http://sqlfiddle.com/#!4/d154c/1
update dataTable a
set ACCR = 15481,
ACCF = 3,
a.ACCX = (
select COUNT(*)
from dataTable b
where b.Account=a.Account)
WHERE a.ID = 1625;
I have a pig relation like below:
FINAL= {input_md5::type: chararray,input_md5::name: chararray,input_md5::id: long,input_md5::age: chararray,test_1:: type: chararray,test_2::name:chararray}
I am trying to store all columns for input_md5 relation to a hive table.
like all input_md5::type: chararray,input_md5::name: chararray,input_md5::id: long,input_md5::age: chararray not taking test_1:: type: chararray,test_2::name:chararray
is there any command in pig which filters only columns of input_md5.Something like below:
STORE= FOREACH FINAL GENERATE all input_md5::type .
I know that pig have :
FOREACH FINAL GENERATE all input_md5::type as type syntax, but i have many columns so I cannot use as in my code.
Because when i try:
STORE= FOREACH FINAL GENERATE input_md5::type .. bus_input_md5::name;
Pig throws an error:
org.apache.hive.hcatalog.common.HCatException : 2007 : Invalid column position in partition schema : Expected column <type> at position 1, found column <input_md5::type>
Thanks in advance,
Resolved this issue , below is the fix:
Create a relation with some filter condition as below:
DUMMY_RELATION= FILTER SOURCE_TABLE BY type== ''; (I took a column named type ,this can be filtered by any column in the table , all that matters is we need its schema)
FINAL_DATASET= UNION DUMMY_RELATION,SCHEMA_1,SCHEMA_2;
(this new DUMMY_RELATIONn should be placed 1st in the union)
Now you no more have :: operator And your column names would match hive table's column names, provided your source table (to DUMMY_RELATION) and target table have same column order.
Thanks to myself :)
I implemented Neethu's example this way. May have typos, but it shows how to implement this idea.
tableA = LOAD 'default.tableA' USING org.apache.hive.hcatalog.pig.HCatLoader();
tableB = LOAD 'default.tableB' USING org.apache.hive.hcatalog.pig.HCatLoader();
--load empty table
finalTable = LOAD 'default.finalTable' USING org.apache.hive.hcatalog.pig.HCatLoader();
--example operations that end up with '::' in column names
g = group tableB by (id);
j = JOIN tableA by id LEFT, g by group;
result = foreach j generate tableA::id, tableA::col2, g::tableB;
--union empty finalTable and result
result2 = union finalTable, result;
--bob's your uncle
STORE result2 INTO 'finalTable' USING org.apache.hive.hcatalog.pig.HCatStorer();
Thanks to Neethu!
I need to update a column in one table with the results from a select sub-query (and they should ultimately be different). But When I do this, I get the 'ORA-01427: single row sub-query returns more than one row query' error.
Can you please take a look and see what it is that I am overlooking? (I could just be overlooking something simple for all I know)
UPDATE AIRMODEL_NETWORK_SUMMARY ans
SET ANS.NBR_RETURNS = (
SELECT SUM(RQ.RETURN_QTY)
FROM RETURN_QTY RQ JOIN AIRMODEL_NETWORK_SUMMARY ANS ON RQ.LOC_ID = ANS.LOC_ID
WHERE RQ.FSCL_YR_NUM = ans.FSCL_YR_NUM
AND RQ.FSCL_WK_IN_YR_NUM =
ans.FSCL_WK_IN_YR_NUM
GROUP BY ANS.LOC_ID,
ans.FSCL_WK_IN_YR_NUM,
ANS.FSCL_YR_NUM
);
I think that your inner query is not well correlated to the table that you're trying to update. Please look here Oracle SQL: Update a table with data from another table. You should add some kind of a where condition that ties the rows you're trying to update with the values calculated by the inner statement.
I would like to achieve same result as the below query using Hibernate SQL, i.e., I would like to get two random records from the table whose ID is not equal to 300. I am using Hibernate 4.1 and Oracle 11g. I ran the below query on Toad and it gives 2 random records. But, when I try to run the HQL, there is error to do with the usage of "DBMS_RANDOM.value".
SELECT * FROM
( SELECT *
FROM table
where ID != '300'
AND q_ID=125
ORDER BY DBMS_RANDOM.value
)WHERE rownum < 3
;
I tried creating criteria and query, but both give Hibernate errors:
Hibernate Message: Invalid path: 'DBMS_RANDOM.RANDOM' [from com.model.table tab where tab.ID != '33092' ORDER BY DBMS_RANDOM.RANDOM]
and my actual hibernate query is:
Query query = session.createQuery("from table tab where tab.ID != '" +agrmId+"' ORDER BY DBMS_RANDOM.RANDOM").setMaxResults(2);
I also tried ORDER BY rand() and that gives an Oracle error.
Thank you for any help.
I solved the problem by adding a property tag in the hibernate mapping file:
<property name="constVal" formula="DBMS_RANDOM.RANDOM" type="long"/>
and then, in the POJO class, I added a variable with getter and setter methods:
private long constVal;
then, in the DAO class, I added the following query:
Criteria crit1 = session.createCriteria(table.class);
crit1.add(Restrictions.ne("id",300));
crit1.add(Restrictions.eq("quesId",125));
crit1.addOrder(Order.asc("constVal"));
crit1.setMaxResults(2);
and that solved it.