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If insert statement gives duplicate key exception(row id=1 found in table) how to update the statement in JDBC(Postgresql)

I have Stored bunch of insert statements in ArrayList.like below
List<String> script=new ArrayList<String>;
script.add("INSERT INTO PUBLIC.EMPLOYEE(ID, NAME) VALUES (1, 'Madhava'));
script.add(INSERT INTO PUBLIC.EMPLOYEE(ID, NAME) VALUES (2, 'Rao'));
script.add(INSERT INTO PUBLIC.ADDRESS(ID, CITY) VALUES(1, 'Bangalore'))
script.add(INSERT INTO PUBLIC.ADDRESS(ID, CITY) VALUES(2, 'Hyd'));
I created connection to the postgresql using jdbc i get executed statments using for loop like below
try{
Connection con=DBConnections.getPostgresConnection();
Statment statment=con.createStatment();
for(String query:script){
executeUpdate(query);
}
}catch(Exception e){
e.printStackTrace();
}
If i get duplication key exception(i.e.Already record exist in postgresDB).
org.postgresql.util.PSQLException: ERROR: duplicate key value
violates unique constraint "reports_uniqueness_index"
How to update the same statment(record) with update query into Postgres.
Is there any way to solve this ?
Is there any other better way to solve this?
Could you please explain...

Execute update sends a DML statement over to the database. Your database must already have a record which uses one of the primary keys either in the employees or address table.
You have to ensure you don't violate the primary key constraint. Violating the constraint is resulting in the exception.
Either change your query to an update statement, or delete the records which are causing conflict.

There is no way to get the key that caused the exception (though you can probably parse the error message, which is certainly not recommended).
Instead, you should try preventing this from ever happenning. There are at least 3 easy ways to accomplish this.
Make the database update the column
(in Postgresql you should use a serial type (which is basically an int data type)
CREATE TABLE employee
(
id serial NOT NULL,
--other columns here )
Your insert will now look like
script.add("INSERT INTO PUBLIC.EMPLOYEE(NAME) VALUES ('Madhava'));//no ID here
Create a sequence and have your JDBC code call the sequence' nexval method.
script.add("INSERT INTO PUBLIC.EMPLOYEE(ID, NAME) VALUES (YOUR_SEQ_NAME.NEXTVAL(), 'Madhava'));
Create a unique ID in Java (least recommended)
script.add("INSERT INTO PUBLIC.EMPLOYEE(ID, NAME) VALUES (UUID.random(), 'Madhava'));//or Math.random() etc

How to find the primary key of deleted records with JDBC.?

I want to know how to find the primary key of the deleted records through the JDBC connection.
If my query like following then what will be the primary key of deleted records?
String sqlDelete = "DELETE FROM devicesequences WHERE deviceId = 20;
What is the primary key of the deleted record?

You need a second query. And of course you need to execute it before running the DELETE query.
SELECT id FROM devicesequences WHERE deviceId = 20;
assuming that id is the name of your primary key column.

Since you can delete any arbitrary row (or set of rows) at any time: no, there's no way to tell WHICH row (or rows) you most recently deleted.
You can, however, create a "trigger" to save this information for you.
http://dev.mysql.com/doc/refman/5.0/en/triggers.html

Updating a SQL table

I am doing a Java program in which I am reading input from some files and if it contains any string that I have in my list I have to update the table with name and its count.
First i created a table as follows
create table mobile(name varchar2(20),count int,primary key(name));
for instance,if I read string like "Sony unviels its new phone", table must be updated with name as sony count as 1.
what my doubt is initially it is an empty table. Can we update it as I said.
Thanks in advance....

First table creation
CREATE TABLE mobile
(
t_name VARCHAR (20),
t_count NUMBER,
PRIMARY KEY (t_name)
);
And insert statement
INSERT INTO mobile
VALUES ('Sony', 1);
Single statement for insert and update
MERGE INTO mobile t
USING (SELECT *
FROM mobile
WHERE LOWER (t_name) = 'sony') s
ON (t.t_name = s.t_name)
WHEN MATCHED
THEN
UPDATE SET t.t_count = t_count+1
WHEN NOT MATCHED
THEN
INSERT (t_name, t_count)
VALUES ('sony', 1);

Either you prepopulate you table with your given word list so something like
CREATE TABLE mobile(
name varchar2(20),
count_column int,
primary key(name)
);
INSERT INTO mobile (name, count_column) VALUES
('Sony', 0);
or you are adding some magic to your Java code which is deciding whether to do an UPDATE or an INSERT.
As an simple would look like theoretical
UPDATE mobile SET count_column to count_column+1 where name = 'Sony';
this will fail if there is none entry given.

You will have to execute an UPSERT like query , since oracle doesn't have it, you have to do a workaround to resolve this. please check this .

Java update when data exists and insert if doesnt [duplicate]

In MySQL, if you specify ON DUPLICATE KEY UPDATE and a row is inserted that would cause a duplicate value in a UNIQUE index or PRIMARY KEY, an UPDATE of the old row is performed. For example, if column a is declared as UNIQUE and contains the value 1, the following two statements have identical effect:
INSERT INTO table (a,b,c) VALUES (1,2,3)
ON DUPLICATE KEY UPDATE c=c+1;
UPDATE table SET c=c+1 WHERE a=1;
I don't believe I've come across anything of the like in T-SQL. Does SQL Server offer anything comparable to MySQL's ON DUPLICATE KEY UPDATE?

I was surprised that none of the answers on this page contained an example of an actual query, so here you go:
A more complex example of inserting data and then handling duplicate
MERGE
INTO MyBigDB.dbo.METER_DATA WITH (HOLDLOCK) AS target
USING (SELECT
77748 AS rtu_id
,'12B096876' AS meter_id
,56112 AS meter_reading
,'20150602 00:20:11' AS time_local) AS source
(rtu_id, meter_id, meter_reading, time_local)
ON (target.rtu_id = source.rtu_id
AND target.time_local = source.time_local)
WHEN MATCHED
THEN UPDATE
SET meter_id = '12B096876'
,meter_reading = 56112
WHEN NOT MATCHED
THEN INSERT (rtu_id, meter_id, meter_reading, time_local)
VALUES (77748, '12B096876', 56112, '20150602 00:20:11');

There's no DUPLICATE KEY UPDATE equivalent, but MERGE and WHEN MATCHED might work for you
Inserting, Updating, and Deleting Data by Using MERGE

You can try the other way around. It does the same thing more or less.
UPDATE tablename
SET field1 = 'Test1',
field2 = 'Test2'
WHERE id = 1
IF ##ROWCOUNT = 0
INSERT INTO tablename
(id,
field1,
field2)
VALUES (1,
'Test1',
'Test2')

SQL Server 2008 has this feature, as part of TSQL.
See documentation on MERGE statement here - http://msdn.microsoft.com/en-us/library/bb510625.aspx

SQL server 2000 onwards has a concept of instead of triggers, which can accomplish the wanted functionality - although there will be a nasty trigger hiding behind the scenes.
Check the section "Insert or update?"
http://msdn.microsoft.com/en-us/library/aa224818(SQL.80).aspx

Complex INSERT query

I'm pretty new to MySQL. I have two related tables, quite common case: Klients(KID, name, surname) and Visits(VID, VKID, dateOfVisit) - VKID is the Klient ID. I have a problem with suitable INSERT query, this is what I want to do:
1.Check if Klient with specific name and surname exists (let's assume that there are no people with the same surnames)
2.If yes, get the ID and do the INSERT to Visits table
3.If no, INSERT new Klient, get the ID and INSERT to Visits.
Is it possible to do in one query?

You would need to use the IF EXIST / NOT EXISTS and use a subquery to check the table. See the reference bwlo
http://dev.mysql.com/doc/refman/5.0/en/exists-and-not-exists-subqueries.html
HTH

The INSERT statement allows only one single target table.
So the query you're looking for is just impossible unless you use triggers or stored procedures.
But such problem is commonly solved using the fallowing small algorithm:
1) insert a record in table [Visits] assuming the parent record does exist in table [Klients]
INSERT INTO Visits (VKID, dateOfVisit)
SELECT KID, NOW()
FROM Klients
WHERE (name=#name) AND (surname=#surname)
2) check the number of inserted records after query (1)
3) if no record has been inserted, then add a new record table [Klients], and then run (1) again.

try something like this
IF (SELECT * FROM `sometable` WHERE name = 'somename' AND surname = 'somesurname') IS NULL THEN
INSERT INTO Table1(name,surname) VALUES ('somename', 'somesurname');
ELSE INSERT INTO visits(kid,name,surname)
SELECT kid, name, surname FROM Table1 WHERE name = 'somename' AND surname = 'somesurname';
END IF;
there is no need to specify 'VALUES' on the second insert
i have not tested it, but this is the general idea of what you are trying to accomplish.

These should be two queries in a transaction:
INSERT INTO Klients (name, surname)
VALUES ('John', 'Doe')
ON DUPLICATE KEY UPDATE
KID = LAST_INSERT_ID(KID);
INSERT INTO Visits (VKID, dateOfVisits)
VALUES (LAST_INSERT_ID(), NOW());
The first statement is an upsert statement where the update part uses not widely known, but intented exactly for the purpose functionality of LAST_INSERT_ID(), where explicitly passed value is stored for getting the value afterwards.
UPD: I forgot to mention that you would need to add a unique constraint on (surname, name).