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Retrieve generated keys from multiple queries in single Spring JDBC Update

I am using a single Spring JDBC update to make an update to two tables in my Postgres database. My SQL query is as follows:
UPDATE accounts SET last_transaction_amount = :transaction_amount WHERE acct_num = :acct_num; INSERT INTO transactions (transaction_amout) VALUES (:transaction_amount);
Using NamedParameterJdbcTemplate#update, I have no issue executing this query and achieving the expected results.
The transactions table generates a sequential transaction identifier, and I want to return this to my application.
I've tried passing a GeneratedKeyHolder in the update call. This is returning the error "A result was returned when none was expected". Docs link.
I've tried passing a GeneratedKeyHolder and array of column names (new String[] {"transaction_id"}). This is returning the error that the column doesn't exist. Note this method call does work to return the transaction id when I only pass the INSERT query without the preceding UPDATE query. Docs link.
How can I retrieve the generated key? Thank you!

You seem to be looking for the RETURNING clause. Assuming that the serial number is called transaction_id:
INSERT INTO transactions (transaction_amout)
VALUES (:transaction_amount)
RETURNING transaction_id;

Update and Return Updated column using returning keyword in same query in java jdbc code

update account set lastusedval=lastusedval+1 where isactive=1 returning
lastusedval;
How to execute above query in java?
when i tried to execute in oracle its working but in java hibernate/jpa no way to store return value in update query.
By executing above query intention is to apply lock on db level when more than 1 request comes

Using jdbc prepared statement with registeroutparameter might help you to resolve this issue.
Creating an UPDATE RETURNING query in Hibernate

JPA Criteria API using ISNULL in a order by statement

I use MySQL 5.5 with Hibernate 3.6 and JPA 2.0. I have a User table with a firstName which could also be null or an empty string. I want to have those empty firstName results last in my search results. For that I wrote the following SQL query which works just fine:
SELECT * FROM User ORDER BY ISNULL(firstName), firstName = "", firstName ASC LIMIT 100
Now want to translate this to JPA using the criteria API and I am not quite so sure about the order by. Here is what I have:
criteriaQuery = criteriaQuery.orderBy(cb.asc(cb.isNull(users.get(User_.firstName))), cb.asc(cb.equal(users.get(User_.firstName), "")), cb.asc(users.get(User_.firstName)));
However, the code snippet above does not work, because the CriteriaBuilder.isNull() method is traslated to IS NULL and not to the ISNULL() function of MySQL. I get the following exception:
org.hibernate.hql.ast.QuerySyntaxException: unexpected AST node: is null
Any ideas on how to check for null in the Order by statement with JPA 2.0

That is not possible. In JPA you can ORDER BY fields only that you select (that are in the SELECT part of your query). The problem is that there is no IS_NULL function, that can be used in the SELECT part.

I got the exact same problem as you do, finally I solve it using this way, maybe you can try:
CriteriaQuery<> query;
query.orderBy(cb.desc(cb.selectCase().
when(cb.isNull("field name"),0).otherwise(1)),
cb.asc("field name");

HibernateTemplate Delete by condition that may include checking NULL

I am trying to write a DAO using Spring's HibernateTemplate that supports deletion from a table based on several conditions. For example, sample SQL:
Delete from Employee where Name='E01' AND Dept='D01' AND Address='ADR01';
I wrote the below code for this query:
session.createQuery("delete from Employee where name=? and dept=? and address=?")
.setParameter(0, name).setParameter(1, dept).setParameter(2, address)
.executeUpdate();
it works fine if all columns in where clause have some values. However, if I try to delete records which have "NULL" in their any column, then it does not work.
The generated SQL Query is always of the form:
Delete from Employee where Name=? AND Dept=? AND Address=?;
which of course cannot handle NULL comparison - SQL requires "IS NULL" for checking NULL and "=null" doesn't do the trick here. So when I pass dept as null in Java code, the generated SQL would be of the form:
Delete from Employee where Name='E01' AND Dept=null AND Address='ADR01';
This does not delete the records from DB which have NULL values in Dept column, as the correct condition would be "Dept IS NULL"; and "Dept=null" does not work! Is there anyway to compare NULL values in where clause without using a native query?
NOTE:
I do not want to use deleteAll(Collection) method of HibernateTemplate, as it requires fetching the records first and then deleting them - i.e. more than 1 SQL query. I want to achieve deletion using a single SQL query, without requiring to select first, or requiring native queries.
I am aware that Spring advices using SessionFactory now, but I am stuck with HibernateTemplate in existing code base.

Which one to use - executeUpate or list - to insert and update and select?

I've written a stored procedure with the following sql statements
insert a row in table a
update a row in table b
insert a row in error table
select query to list the number of records in the error table
Can i use query.list() ? Will it does all the inserts, updates and returns the list properly?
I think we cannot use query.executeUpdate() as it returns only number of rows updated or inserted at last sql statement.
Thanks in advance,
Kathir

If it is stored procedure you can use do like this
try
{
con = connectionPool.getConnection();
proc = con.prepareCall("{ call set_death_age(?, ?) }");
proc.setString(1, dyingBard.getName());
proc.setInt(2, age);
proc.execute();
}
catch (SQLException e) {}

http://www.mkyong.com/hibernate/how-to-call-store-procedure-in-hibernate/
See above link for sample of how to call stored procedures with hibernate
if you are using spring, you can call stored procedures via Spring JdbcTemplate as well.