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Oracle - update record and return updated date in same query

I'm using Java 8 with Spring's JdbcTemplate and Oracle 12.1,
I want to update record and get the exact time record was updated
jdbcTemplate.update(UPDATE_SQL, null);
Currently it returns (int) the number of rows affected, but I want the exact updated date
Must I send a new request to get current time which may be inaccurate?
More exact will be to save in column updated date, but then to execute another SQL
Is there another option to get updated date in one query?
Obviously, I don't want to use get date from code also (as new Date()) also because server time is/can be different than DB Time

You decided to use JDBCTemplate most probably to simplify the code in comparison to plain JDBC.
This particular problem IMHO makes the plain JDBC solution as proposed in other answer much simpler, so I'd definitively recommend to get the database connection from JDBCTemplate and make the insert in a JDBC way.
The simplest solution using JDBCTemplate that comes to my mind is to wrap the insert in a PROCEDURE and return the timestamp as an OUT parameter.
Simple example (Adjust the time logik as required)
create procedure insert_with_return_time (p_str VARCHAR2, p_time OUT DATE) as
BEGIN
insert into identity_pk(pad) values(p_str);
p_time := sysdate;
END;
/
The call is done using SimpleJdbcCall
SimpleJdbcCall jdbcCall = new SimpleJdbcCall(jdbcTemplate).withProcedureName("insert_with_return_time");
SqlParameterSource params = new MapSqlParameterSource().addValue("p_str", str);
Map<String, Object> out = jdbcCall.execute(params);
The Map contains the returned value e.g. [P_TIME:2019-10-19 11:58:10.0]
But I can only repeat, in this particular use case is IMHO JDBC a rescue from JDBCTemplate;)

You're right that passing new Date() would store the server time rather than the DB time.
To store the DB time you can set your timestamp to the DB system timestamp systimestamp then you could run a query to retrieve that row and its updated timestamp.
If you want to update the row and get the updated timestamp in a single execution then you could do the following using RETURNING INTO where TimestampUpdated is your column name:
Connection con = ...;
String sql = "UPDATE TableName SET <updates> , TimestampUpdated = systimestamp RETURNING TimestampUpdated INTO ?";
CallableStatement statement = con.prepareCall(sql);
statement.registerOutParameter(1, Types.TIMESTAMP);
int updateCount = statement.executeUpdate();
Timestamp timestampUpdated = statement.getInt(1);
System.out.println("Timestamp Updated = " + timestampUpdated);
Here is a related link doing this with JdbcTemplate

How To Fetch Updated Rows In JDBC [duplicate]

I'm using Java 8 with Spring's JdbcTemplate and Oracle 12.1,
I want to update record and get the exact time record was updated
jdbcTemplate.update(UPDATE_SQL, null);
Currently it returns (int) the number of rows affected, but I want the exact updated date
Must I send a new request to get current time which may be inaccurate?
More exact will be to save in column updated date, but then to execute another SQL
Is there another option to get updated date in one query?
Obviously, I don't want to use get date from code also (as new Date()) also because server time is/can be different than DB Time

You decided to use JDBCTemplate most probably to simplify the code in comparison to plain JDBC.
This particular problem IMHO makes the plain JDBC solution as proposed in other answer much simpler, so I'd definitively recommend to get the database connection from JDBCTemplate and make the insert in a JDBC way.
The simplest solution using JDBCTemplate that comes to my mind is to wrap the insert in a PROCEDURE and return the timestamp as an OUT parameter.
Simple example (Adjust the time logik as required)
create procedure insert_with_return_time (p_str VARCHAR2, p_time OUT DATE) as
BEGIN
insert into identity_pk(pad) values(p_str);
p_time := sysdate;
END;
/
The call is done using SimpleJdbcCall
SimpleJdbcCall jdbcCall = new SimpleJdbcCall(jdbcTemplate).withProcedureName("insert_with_return_time");
SqlParameterSource params = new MapSqlParameterSource().addValue("p_str", str);
Map<String, Object> out = jdbcCall.execute(params);
The Map contains the returned value e.g. [P_TIME:2019-10-19 11:58:10.0]
But I can only repeat, in this particular use case is IMHO JDBC a rescue from JDBCTemplate;)

You're right that passing new Date() would store the server time rather than the DB time.
To store the DB time you can set your timestamp to the DB system timestamp systimestamp then you could run a query to retrieve that row and its updated timestamp.
If you want to update the row and get the updated timestamp in a single execution then you could do the following using RETURNING INTO where TimestampUpdated is your column name:
Connection con = ...;
String sql = "UPDATE TableName SET <updates> , TimestampUpdated = systimestamp RETURNING TimestampUpdated INTO ?";
CallableStatement statement = con.prepareCall(sql);
statement.registerOutParameter(1, Types.TIMESTAMP);
int updateCount = statement.executeUpdate();
Timestamp timestampUpdated = statement.getInt(1);
System.out.println("Timestamp Updated = " + timestampUpdated);
Here is a related link doing this with JdbcTemplate

Query with NOW() in criteria behaves differently in psql vs. JDBC

I am executing following query in psql via console and getting output :
select details
from history_transactions
,history_operations
where history_operations.transaction_id = history_transactions.id
and type = 3
and created_at >= NOW() - INTERVAL '5 minutes'
However when I call this code from my java program, it is not returning any output. The ResultSet is null. PFB my code:
Connection conn = getConnection();
java.sql.Statement stmt = null;
String sql ="select details from history_transactions , history_operations where history_operations.transaction_id=history_transactions.id and type =3 and created_at >= NOW() - INTERVAL '5 minutes'";
try{
stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
while(rs.next()) {
System.out.println("Inside resultset");
}
}
catch(Exception e)
{
e.printStackTrace();
}
Any idea where I am going wrong?
I am not getting any exception as well.
Note: If I change the interval from 5 minute to 6 hours or more it is working and giving me output. If I change the interval < 5 hours then the resultset is null. However If I login to psql server and execute the query as it is in the code. I am getting output.
I am using java version "1.8.0_151" and PostgreSQL JDBC 4.2 Driver, 42.2.1 - as per https://jdbc.postgresql.org/download.html - it is the suitable driver.

The PostgreSQL NOW() function returns a timestamp with time zone value. In order to use that value against a column of type timestamp (without time zone) PostgreSQL needs to implicitly CAST that value to match the column type. However, testing shows that if the client and the server are set to different time zones the result of that CAST can be different when connected via psql vs. when connected via JDBC. For example:
Server time zone: UTC
Client time zone: America/Denver, a.k.a. "MST/MDT", currently UTC-7
When connected via psql,
SELECT CAST(CAST(NOW() AS timestamp) AS varchar)
returns the UTC value
2018-02-05 22:40:25.012933
but when connected via JDBC the same query returns the MST value
2018-02-05 15:40:57.288587
To return the UTC value under JDBC we can execute
set time zone 'UTC'
before running our SELECT query.

different results from query in java code and on oracle db server: but no connection error

I have java code that connects to a remote oracle 11g EE db server. If i run a particular query in sqlplus it returns one result
SQL> SELECT COURSENAME from COURSES where skillID=1;
COURSENAME
--------------------
basic
But if I run the same query from the java code below it returns no results. I can copy the query syntax out of the query variable in the java debugger and running it on oracle so I know there is no syntax issue with the query. Also, it is not SQL exceptions or class not found exceptions so it seems to be running the query successfully -- just returning zero results.
What might be going on?
private String getCourseForSkill(int skillID){
try{
Class.forName("oracle.jdbc.OracleDriver");
String query="SELECT COURSENAME from COURSES where skillID=" + skillID ;
con = DriverManager.getConnection(url, user, password);
Statement stmt = con.createStatement();
rs = stmt.executeQuery(query);
rs.next();
return rs.getString("COURSENAME");
}
catch (ClassNotFoundException ex){
System.out.println(ex.getMessage());
}
catch (SQLException ex) {
System.out.println(ex.getMessage());
}
return null;
}

I think you're connecting to different Oracle instances, or more likely, as different Oracle users in the two cases
#GreyBeardedGeek the URL looks like "jdbc:oracle:thin:#website:port:orcl I get to the manual query by doing ssh#website, authenticating and then running command=sqlplus
Safer to run sqlplus <username>/<password>#<orainstancename>, because you can explicitly specify the oracle instance ID. In your case, it seems your program is using jdbc connection jdbc:oracle:thin:#website:port:orcl, so your orainstancename would be 'orcl' - just ensure that your tnsnames.ora file has the instance 'orcl' with the same 'port' as used by the jdbc connection
How to debug a little more
Run the following code:
con = DriverManager.getConnection(url, user, password);
con.setAutoCommit(false);
String insert="INSERT INTO COURSES (SKILLID, COURSE)"+ // can add other columns
"values (?, ?) );" // add ? for other columns
PreparedStatement ps = con.createPreparedStatement();
ps.setInt(1, 999);
ps.setString(2, "Complete Bullwarks");
// can set other columns
ps.executeUpdate(insert);
con.commit();
NOW connect manually, re-run your original select statement & see if the added row is there. If no error in java and no new row in Oracle: extremely likely you're using 2 different Oracle instances/schemas.
ALSO rerun your original java select code, but with SkillID=999 - extremely likely it will work.
Cheers

I had to do a commit to add the rows. When I typed commit; into the sql plus terminal then the remote jdbc connection could 'see' the rows. I am used to SQL server where you don't have to explicitly do these kinds of commits when using linq-to-sql or sql management studio.

It can be three issues.
1) skillID <> 1 in your Java code. Add debug and check.
2a) You are connecting to another database.
2b) You are connecting to the same database but SELECTING from a table in another schema.
To check 2a and 2b:
select user from dual; -- connect username
select name from v$database; -- database name
select host_name from v$instance; -- host name database is running on
This query returns all three into one result.
select user || '' || d.name || '' || i.host_name
from v$database d, v$instance i;

Assuming you are actually connecting to the same database this is caused by not committing the INSERT in the sql*plus connection.
Oracle by default does not run in auto-commit mode when connecting via OCI (which sql*plus uses to connect). Any DML(INSERT ...) executed in sql*plus will not be visible to any other session until it is committed. This is because Oracle provides a read committed isolation level by default. The only thing visible to other users across sessions are write locks.
It doesn't matter if you connect the second connection via JDBC or OCI, it won't see the changes till you commit the first connection.
To test this out try opening 2 sql*plus connections and run the following:
-- Executing DDL in Oracle causes an implicit commit before and after the
-- command so the second connection will see the existence of this table:
CREATE TABLE foobar ( x VARCHAR(1) );
Execute this in connection #1 - you should get zero (we haven't inserted anything yet):
SELECT COUNT(*) FROM foobar;
Execute this in connection #2:
INSERT INTO foobar ( x ) VALUES ( 'A' );
Execute this in connection #1 - you should still get zero (INSERT is not committed so connection #1 cannot see it):
SELECT COUNT(*) FROM foobar;
Execute this in connection #2:
COMMIT;
Execute this in connection #1 - you should get 1 (it's committed now):
SELECT COUNT(*) FROM foobar;

Java Oracle jdbc COLUMN statement

The problem is following
By executing the below queries in SQL Plus, everything is working perfect:
column firstname new_value v_firstname
select firstname from tbcustomer where customer_id = 111
select '&v_firstname', wrk.* from tbwork where customer_id = 111
But when when i tried to execute these queries from Java program, i get java.sql.SQLException: ORA-00900: invalid SQL statement on the first SQL query
Connection connection = null;
Statement stat = null;
String query = "column due_date new_value v_due_date";
try {
// Load the JDBC driver
String driverName = "oracle.jdbc.driver.OracleDriver";
Class.forName(driverName);
connection = DriverManager.getConnection(url, username, password);
stat = connection.createStatement();
boolean res_num = stat.execute(query);
} catch (ClassNotFoundException e) {
// Could not find the database driver
} catch (SQLException e) {
e.printStackTrace();
}
Now the question is how to overcome this error and execute first query or do you have any other solution to define variable on the oracle session and use it in other SQL statements.
For instance third query is one of the many queries that i need to execute and all of them will have same first name field

column is a SQL*Plus command. It is not valid in SQL or PL/SQL so you cannot use it in a Java application.
Substitution variables like &v_firstname are also a SQL*Plus construct-- they are not valid in SQL or PL/SQL so you cannot use them in a Java application.
If your goal is to get the firstname from tbcustomer and all the columns from tbwork in a single query, you would need to join the two tables. Assuming that both tables have a customer_id column and that is how the two tables are supposed to be joined
SELECT cust.firstname,
work.*
FROM tbcustomer cust
JOIN tbwork work ON (cust.customer_id = work.customer_id)
WHERE cust.customer_id = 111
Assuming that you will be executing this query for multiple customer_id values, however, 111 should be a bind variable instead of a literal and your Java code should be using a PreparedStatement to prepare the SQL statement, then binding a value like 111 using the setInt method before executing the query.
If you want to break this into two database calls, you can simply do something like
PreparedStatement stmtGetFirstName = connection.prepareStatement("select firstname from tbcustomer where customer_id = ?");
stmtGetFirstName.setInt( 1, 111 );
ResultSet rsGetFirstName = stmtGetFirstName.executeQuery();
String firstName = rsGetFirstName.getString();
PreparedStatement stmtGetWork = connection.prepareStatement("select ?, work.* from tbwork where customer_id = ?");
stmtGetWork.setString( 1, firstName );
stmtGetWork.setInt( 2, 111 );
ResultSet rsGetWork = stmtGetWork.executeQuery();
If you can guarantee that all 600 million executions will occur in the same database session, you could use a database context. You would need to create the context and the package it uses in the database
SQL> create or replace context fname_ctx using scott.pkg_get_fname;
Context created.
SQL> ed
Wrote file afiedt.buf
1 create or replace package pkg_get_fname
2 is
3 procedure set_fname( p_customer_id in number );
4 function get_fname return varchar2;
5* end;
SQL> /
Package created.
SQL> create or replace package body pkg_get_fname
2 is
3 procedure set_fname( p_customer_id in number )
4 as
5 begin
-- Obviously, you'd get the data here from your table rather than hard-coding 'Bob'
6 dbms_session.set_context( 'fname_ctx', 'fname', 'Bob' );
7 end;
8
9 function get_fname
10 return varchar2
11 is
12 l_fname varchar2(100);
13 begin
14 l_fname := sys_context( 'fname_ctx', 'fname' );
15 return l_fname;
16 end;
17 end;
18 /
Package body created.
From Java, you could then call pkg_get_fname.set_fname(111) to set the context and use the function pkg_get_fname.get_fname in your query.
It seems odd, however, to be concerned about performance and to be planning to execute 600 million queries from Java against the database. That's going to involve a ton of round-trips over the network between the middle tier and the database server-- if you're really concerned about performance, you'd push that work to stored procedures in the database to eliminate the network round-trips. And the fact that you're executing them so many times makes me suspect that you're doing a lot of row-by-row processing rather than letting the database do set-based operations. That's also going to be a major source of poor performance. Plus, databases are born to join, so it's pretty unusual for a simple join like this to add appreciably to the cost of a query assuming that proper indexes are in place.