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How to insert/update a single record using a MERGE statement with Spring JDBC

I have an update/insert SQL query that I created using a MERGE statement. Using either JdbcTemplate or NamedParameterJdbcTemplate, does Spring provide a method that I can use to update a single record, as opposed to a Batch Update?
Since this query will be used to persist data from a queue via a JMS listener, I'm only dequeuing one record at a time, and don't have need for the overhead of a batch update.
If a batch is the only way to do it through Spring JDBC, that's fine... I just want to make certain I'm not missing something simpler.

You can use a SQL MERGE statment using only a one row query containing your parameters.
For example if you have a table COMPANYcontaing IDas a key and NAMEas an attribute, the MERGE statement would be:
merge into company c
using (select ? id, ? name from dual) d
on (c.id = d.id)
when matched then update
set c.name = d.name
when not matched then insert (c.id, c.name)
values(d.id, d.name)
If your target table contains the parametrised key, the name will be updated, otherwise a new record will be inserted.
With JDBCTemplate you use the update method to call the MERGEstatement, as illustrated below (using Groovy script)
def id = 1
def name = 'NewName'
String mergeStmt = """merge into company c
using (select ? id, ? name from dual) d
on (c.id = d.id)
when matched then update
set c.name = d.name
when not matched then insert (c.id, c.name)
values(d.id, d.name)""";
def updCnt = jdbcTemplate.update(mergeStmt, id, name);
println "merging ${id}, name ${name}, merged rows ${updCnt}"

Just use one of update methods, for example this one: JdbcTemplate#update instead of BatchUpdate.
Update updates a single record, batchUpdate updates multiple records using JDBC batch

Are mutliple statements without transaction possible using jdbcTemplate

I am trying to update 2 tables at the same time where the inserted index of the first should be inserted into the 2nd table.
The sql looks like this:
DECLARE #nrTable table (TXT_nr int)
IF NOT EXISTS (SELECT txt FROM tbl1 WHERE txt = (?))
INSERT INTO tbl1 (txt, new) OUTPUT INSERTED.nr INTO #nrTable VALUES((?), 1)
IF NOT EXISTS (SELECT txt FROM tbl1 WHERE txt =(?))
INSERT INTO tbl2 (TXT_nr, field1, field2)
VALUES((SELECT TXT_nr FROM #nrTable), (?), (?))
WHERE field3 = (?) AND field4 = (?)
I am trying to accomplish this using
this.jdbcTemplate.batchUpdate(sql, batch);
simply concatenating the lines in java using basic strings. This seems to only execute the first statement, though.
Now the reason I don´t want to do this transactionally is that I would have to do it using a loop just inserting one batch-object at a time, because of the ouput-clause. This would result in loads of calls to the sql-server.
Is there any known way to accomplish something like this?

You can't use batchupdate in this way. Please refer to this document http://tutorials.jenkov.com/jdbc/batchupdate.html
And to achieve your goal, if you are using a sequence in sql, then you need to get the new value in java and store it in your query. Like this :
long id = jdbcTemplace.queryForObject("select sequence_name.nextval from dual",Long.class);

How to upsert(update if exists, else insert) into a table using jdbcTemplate [duplicate]

The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data:
if table t has a row exists that has key X:
update t set mystuff... where mykey=X
else
insert into t mystuff...
Since Oracle doesn't have a specific UPSERT statement, what's the best way to do this?

The MERGE statement merges data between two tables. Using DUAL
allows us to use this command. Note that this is not protected against concurrent access.
create or replace
procedure ups(xa number)
as
begin
merge into mergetest m using dual on (a = xa)
when not matched then insert (a,b) values (xa,1)
when matched then update set b = b+1;
end ups;
/
drop table mergetest;
create table mergetest(a number, b number);
call ups(10);
call ups(10);
call ups(20);
select * from mergetest;
A B
---------------------- ----------------------
10 2
20 1

The dual example above which is in PL/SQL was great becuase I wanted to do something similar, but I wanted it client side...so here is the SQL I used to send a similar statement direct from some C#
MERGE INTO Employee USING dual ON ( "id"=2097153 )
WHEN MATCHED THEN UPDATE SET "last"="smith" , "name"="john"
WHEN NOT MATCHED THEN INSERT ("id","last","name")
VALUES ( 2097153,"smith", "john" )
However from a C# perspective this provide to be slower than doing the update and seeing if the rows affected was 0 and doing the insert if it was.

An alternative to MERGE (the "old fashioned way"):
begin
insert into t (mykey, mystuff)
values ('X', 123);
exception
when dup_val_on_index then
update t
set mystuff = 123
where mykey = 'X';
end;

Another alternative without the exception check:
UPDATE tablename
SET val1 = in_val1,
val2 = in_val2
WHERE val3 = in_val3;
IF ( sql%rowcount = 0 )
THEN
INSERT INTO tablename
VALUES (in_val1, in_val2, in_val3);
END IF;

insert if not exists
update:
INSERT INTO mytable (id1, t1)
SELECT 11, 'x1' FROM DUAL
WHERE NOT EXISTS (SELECT id1 FROM mytble WHERE id1 = 11);
UPDATE mytable SET t1 = 'x1' WHERE id1 = 11;

None of the answers given so far is safe in the face of concurrent accesses, as pointed out in Tim Sylvester's comment, and will raise exceptions in case of races. To fix that, the insert/update combo must be wrapped in some kind of loop statement, so that in case of an exception the whole thing is retried.
As an example, here's how Grommit's code can be wrapped in a loop to make it safe when run concurrently:
PROCEDURE MyProc (
...
) IS
BEGIN
LOOP
BEGIN
MERGE INTO Employee USING dual ON ( "id"=2097153 )
WHEN MATCHED THEN UPDATE SET "last"="smith" , "name"="john"
WHEN NOT MATCHED THEN INSERT ("id","last","name")
VALUES ( 2097153,"smith", "john" );
EXIT; -- success? -> exit loop
EXCEPTION
WHEN NO_DATA_FOUND THEN -- the entry was concurrently deleted
NULL; -- exception? -> no op, i.e. continue looping
WHEN DUP_VAL_ON_INDEX THEN -- an entry was concurrently inserted
NULL; -- exception? -> no op, i.e. continue looping
END;
END LOOP;
END;
N.B. In transaction mode SERIALIZABLE, which I don't recommend btw, you might run into
ORA-08177: can't serialize access for this transaction exceptions instead.

I'd like Grommit answer, except it require dupe values. I found solution where it may appear once: http://forums.devshed.com/showpost.php?p=1182653&postcount=2
MERGE INTO KBS.NUFUS_MUHTARLIK B
USING (
SELECT '028-01' CILT, '25' SAYFA, '6' KUTUK, '46603404838' MERNIS_NO
FROM DUAL
) E
ON (B.MERNIS_NO = E.MERNIS_NO)
WHEN MATCHED THEN
UPDATE SET B.CILT = E.CILT, B.SAYFA = E.SAYFA, B.KUTUK = E.KUTUK
WHEN NOT MATCHED THEN
INSERT ( CILT, SAYFA, KUTUK, MERNIS_NO)
VALUES (E.CILT, E.SAYFA, E.KUTUK, E.MERNIS_NO);

I've been using the first code sample for years. Notice notfound rather than count.
UPDATE tablename SET val1 = in_val1, val2 = in_val2
WHERE val3 = in_val3;
IF ( sql%notfound ) THEN
INSERT INTO tablename
VALUES (in_val1, in_val2, in_val3);
END IF;
The code below is the possibly new and improved code
MERGE INTO tablename USING dual ON ( val3 = in_val3 )
WHEN MATCHED THEN UPDATE SET val1 = in_val1, val2 = in_val2
WHEN NOT MATCHED THEN INSERT
VALUES (in_val1, in_val2, in_val3)
In the first example the update does an index lookup. It has to, in order to update the right row. Oracle opens an implicit cursor, and we use it to wrap a corresponding insert so we know that the insert will only happen when the key does not exist. But the insert is an independent command and it has to do a second lookup. I don't know the inner workings of the merge command but since the command is a single unit, Oracle could execute the correct insert or update with a single index lookup.
I think merge is better when you do have some processing to be done that means taking data from some tables and updating a table, possibly inserting or deleting rows. But for the single row case, you may consider the first case since the syntax is more common.

A note regarding the two solutions that suggest:
1) Insert, if exception then update,
or
2) Update, if sql%rowcount = 0 then insert
The question of whether to insert or update first is also application dependent. Are you expecting more inserts or more updates? The one that is most likely to succeed should go first.
If you pick the wrong one you will get a bunch of unnecessary index reads. Not a huge deal but still something to consider.

Try this,
insert into b_building_property (
select
'AREA_IN_COMMON_USE_DOUBLE','Area in Common Use','DOUBLE', null, 9000, 9
from dual
)
minus
(
select * from b_building_property where id = 9
)
;

From http://www.praetoriate.com/oracle_tips_upserts.htm:
"In Oracle9i, an UPSERT can accomplish this task in a single statement:"
INSERT
FIRST WHEN
credit_limit >=100000
THEN INTO
rich_customers
VALUES(cust_id,cust_credit_limit)
INTO customers
ELSE
INTO customers SELECT * FROM new_customers;

Merge values to table from Java

I have a java program that reads a csv file line by line and does MERGE in the table using the Merge statement provided by DB2.
For example, If i have a 1000 lines in CSV it would run the executeUpdate 1000 times.
My challenge is that i run this script every hour so there is a possibility that new entries would come into the csv file or values would get updated or rows might be deleted (sometimes the row will come again in future)
I think i am doing the insert if not exist and update if exist part correct but i am not sure how do i do the delete part for rows that were inserted in the past but no longer in the latest csv file ?
Also what would be an ideal situation here to avoid doing 1000 insert statement do i use prepared statement ? Can someone give me an example ?
String sql_merge = " MERGE INTO IM4BMX.IEMCOMPUTER_DETAILS AS A USING (VALUES ('"+ComputerID+"', '"+Environment+"')) AS A_TMP ( ComputerID , Environment) ON A.ComputerID = A_TMP.ComputerID WHEN MATCHED THEN UPDATE SET ComputerID = '"+ComputerID+"', Environment = '"+Environment+"' WHEN NOT MATCHED THEN INSERT ( ComputerID , Environment ) VALUES (A_TMP.ComputerID, A_TMP.Environment ) ELSE IGNORE ";
stmt.executeUpdate(sql_merge);

Try adding a when not matched clause to your query.
Ex. WHEN NOT MATCHED
THEN DELETE
If you CSV file contains data that does not match what is in the DB then it should delete that row.
Look at this link for further information.
Merge Statement Explained

JDBC: multicolumn IN query

I have a following query:
SELECT
date, userId, value
FROM
tbl_table
WHERE
date = to_date(:date, 'YYYY-MM-DD')
AND
userId = :userId
It allows to request for a single value like this:
MapSqlParameterSource args = new MapSqlParameterSource();
args.addValue("date", date, Types.VARCHAR);
args.addValue("userId", userId, Types.VARCHAR);
SqlRowSet rowSet = jdbcTemplate.queryForRowSet(SQL_SELECT, args);
jdbcTemplate.queryForRowSet(SQL_SELECT_MARKET_VALUE, args);
This is totally ok, but extremelly slow in case you have to query value for many date/userId pairs.
I would like to optimize it using multicolumn IN clause, but how do I handle multicolumn list via JDBC (or better question: is it possible using JDBC)?

Oracle supports multiple columns in "in" predicate:
SELECT
date, userId, value
FROM
tbl_table
WHERE
(date, userId) IN ((to_date(:date1, 'YYYY-MM-DD'), :userId1), (to_date(:date2, 'YYYY-MM-DD'), :userId2))
However JDBC doesn't provide a decent support of in-statement parameters - you will have to build the query using StringBuilder or use some of workarounds described here

It depends of details. If user/date filter is quite persistent (should be user more than once) temporary table will be the best decision. You can fill it once, you can edit it, and you can use it several times without reloading.
If you need of quite large number of pairs, I'd recommend you to use a table type. It would be something like this:
create type DateUserPair as object (dt date, userid integer);
create type DateUserPairs as table of DateUserPair;
....
SELECT
date, userId, value
FROM
tbl_table src,
table(cast :filter as DateUserPairs) flt
WHERE
src.date = flt.dt and
src.userId = flt.userId;
If filter would be small, filtering by (date, userId) in ((?,?), (?,?), ...) would be simple and clever.
Btw, your approach
date = to_date(:date, 'YYYY-MM-DD')
isn't good practise. Such conversions should be done by client, not by server. Use
date = :date
and assign it as date instead.

If what you want is to pass JDBC a list of date/userId pairs, or a list of dates and a list of userIds, I think it will not work.
A possible workaround in Oracle would be using a global temporary table with ON COMMIT DELETE ROWS. Your would have:
-- DDL for the workaround
CREATE GLOBAL TEMPORARY TABLE admin_work_area
(d DATE,
userId VARCHAR2(10))
ON COMMIT DELETE ROWS;
...
-- Start of query method pseudo-code
...
-- You should be able to JDBC-batch these for better performance
INSERT INTO temp_multicolumn_filter (d, userId) VALUES (date1, userId1);
INSERT INTO temp_multicolumn_filter (d, userId) VALUES (date2, userId2);
...
-- Query using temp_multicolumn_filter
SELECT date, userId, value
FROM tbl_table
WHERE
(date, userId) in (select d, userId from temp_multicolumn_filter);
...
-- End of query method pseudo-code
As the temporary table has the ON COMMIT DELETE ROWS, each transaction will only see its own date/userId pairs. Just remember that if you use the temporary table more than once in the same transaction, you might need to clear it before using it.
UPDATE:
Another option would be using a PIPELINED PL/SQL function to "build" your table inside the query:
-- DDL for this workaround
CREATE TYPE date_userid_pair AS OBJECT (
d DATE,
userId VARCHAR2(10));
CREATE TYPE date_userid_dataset IS TABLE OF date_userid_pair;
CREATE FUNCTION decode_date_userid_pairs(dates in varchar2, userIds in varchar2)
RETURN date_userid_dataset PIPELINED IS
result_row date_userid_pair;
BEGIN
WHILE there are more "rows" in the parameters LOOP
result_row.d := -- Decode next date from dates
result_row.userId := -- Decode next userId from userIds
PIPE ROW(result_row);
END LOOP;
END;
// Start of query method pseudo-code
...
// This is Java code: encodeList encodes a List of elements into a String.
encodedDates = encodeList(listOfDates);
encodedUserIds = encodeList(listOfUserIds);
...
// Query using temp_multicolumn_filter
SELECT date, userId, value
FROM tbl_table
WHERE
(date, userId) in (
select date, userId
from TABLE(decode_date_userid_pair(:encodedDates, :encodedUserIds));
...
// End of query method pseudo-code
But this is more hacky, and if you don't have privileges to create a temporary table, then you probably won't have CREATE TYPE either (you might not even have CREATE FUNCTION privilege).