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Duplicate entry whice using distinct keyword in query

I am using java to execute some SQL Queries. Some of them are Getting data from one database(A) and storing in a table in another database(B).After process is done i am deleting all data from table in database(B). I am repeating this process every 5 mins.
Code:
String sql = "delete from newtable";
stmt5 = conn.prepareStatement(sql);
stmt5.executeUpdate(sql);
String sql_1 = "select distinct tbl_alm_log_2000000000.Csn, tbl_alm_log_2000000000.IsCleared, tbl_alm_log_2000000000.Id,tbl_alm_log_2000000000.NEType, tbl_alm_log_2000000000.OccurTime, tbl_alm_log_2000000000.hostIP, tbl_alm_log_2000000000.ExtendInfo From fmdb.dbo.tbl_alm_log_2000000000 Where IsCleared = 0";
ResultSet rs = stmt_1.executeQuery(sql_1);
String sql_2 = "insert into newtable (CSN, IsCleared, Id, NEType, OccurTime, hostIP) values(?,?,?,?,?,?)";
conn.setAutoCommit(false);
PreparedStatement ps = conn.prepareStatement(sql_2);
final int batchSize = 1000;
int count = 0;
while (rs.next()){
ps.setString(1, rs.getString(1)); //csn
ps.setString(2, rs.getString(2)); //iscleared
ps.setString(3, rs.getString(3));//id
ps.setString(4, rs.getString(4));//netype
ps.setString(5, rs.getString(5));//occurtime
ps.setString(6, rs.getString(6));//hostip
ps.addBatch();
if(++count % batchSize == 0) {
ps.executeBatch();
}
}
ps.executeBatch(); // insert remaining records
conn.commit();
ps.close();
It runs perfectly for 10 -20 runs and then gives "duplicate entry error for "value" in Csn as it is Primary key".
I added Distinct keyword in query and it is still giving this error after 10-20 runs.
Note: I m deleting data from newtable befor start of process so it is always adding in a empty table.
Suggest where i am going wrong.

Looks like you have misunderstanding about how does distinct work. In query with several selected columns it will search for distinct tuples of values, not for distinct Csn column only.
There are different ways how to select distinct values by one column only. It generally depends on particular DBMS you use and logic you want to apply for multiply tuples found for same Csn column values. Consider for instance this question: DISTINCT for only one Column
One of general ideas: select distinct single values for Csn column only, then iterate through this list and select first tuple of values with this Csn value (I don't know is it suitable for you select first tuple or not).

when you insert the data , you can add if not exists not make sure your data is unique ( i considered CSN only column in PK)
if not exists(select 1 from tbl_alm_log_2000000000 where CSN=? )
insert into newtable (CSN, IsCleared, Id, NEType, OccurTime, hostIP) values(?,?,?,?,?,?)

Insert performance tuning

Currently we are selecting data from one database and inserting it into a backup database(SQL SERVER).
This data always contains more than 15K records in one select.
We are using Enumeration to iterate over the data selected.
We are using JDBC PreparedStatement to insert data as:
Enumeration values = ht.elements(); -- ht is HashTable containing selected data.
while(values.hasMoreElements())
{
pstmt = conn.prepareStatement("insert query");
pstmt.executeUpdate();
}
I am not sure if this is the correct or efficient way to do the faster insert.
For inserting 10k rows it takes near about 30 min or more.
Is there any efficient way to make it fast?
Note: Not using any indexes on the table.

Use a batch insert, but commit after a few entris, don't try to send all 10K at once. Try investigating to get the best size, it' a trade off to memory vs network trips.
Connection connection = new getConnection();
Statement statement = connection.createStatement();
int i = 0;
for (String query : queries) {
statement.addBatch("insert query");
if ((i++ % 500) == 0) {
// Do an execute now and again, don't send too many at once
statement.executeBatch();
}
}
statement.executeBatch();
statement.close();
connection.close();
Also, from your code I'm not sure what you are doing, but use paramaterised queries rather than sending 10K insert statements as text. Something like:
String q= "INSERT INTO data_table (id) values (?)";
Connection connection = new getConnection();
PreparedStatement ps = connection.prepareStatement(q);
for (Data d: data) {
ps.setString(1, d.getId());
ps.addBatch();
}
ps.executeBatch();
ps.close();
connection.close();

You can insert all the values in one sql command:
INSERT INTO Table1 ( Column1, Column2 ) VALUES
( V1, V2 ), ( V3, V4 ), .......
You may also insert the values by bulks of 500 records, for example, if the query would become very big. It is not efficient at all to insert on row per statement remotely (using a connection). Another solution is to do the inserts using a stored procedure. You just pass the values to it as parameters.
Here is how you can do it using the INSERT command above:
Enumeration values = ht.elements(); -- ht is HashTable containing selected data.
int i=0;
String sql="";
while(values.hasMoreElements())
{
sql+="(" + values + ")"; //better use StringBuffer here
i++;
if(i % 500 == 0) {
pstmt = conn.prepareStatement("insert query "+sql);
pstmt.executeUpdate();
sql="";
}
else
sql += " , ";
}

SQL - how to return multiple rows with one SQL query?

I have a managed bean which makes SQL queries to Oracle database. This is just very simple example how I make SQL queries. This is the table structure:
GLOBALSETTINGS
---------------------------------
SessionTTL VARCHAR2(40 BYTE)
MAXACTIVEUSERS NUMBER
ACTIVEUSERS VARCHAR2(20 BYTE)
I use this table just to store application settings. In the example listed below I can fetch just one string with one SQL statement. I want with SQL query to fetch the content of the three rows - SessionTTL, MAXACTIVEUSERS, ACTIVEUSERS. Is it possible?
public String CheckUserDB(String userToCheck) throws SQLException {
String storedPassword = null;
String SQL_Statement = null;
if (ds == null) throw new SQLException();
Connection conn = ds.getConnection();
if (conn == null) throw new SQLException();
try {
conn.setAutoCommit(false);
boolean committed = false;
try {
SQL_Statement = "SELECT Passwd from USERS WHERE Username = ?";
PreparedStatement passwordQuery = conn.prepareStatement(SQL_Statement);
passwordQuery.setString(1, userToCheck);
ResultSet result = passwordQuery.executeQuery();
if(result.next()){
storedPassword = result.getString("Passwd");
}
conn.commit();
committed = true;
} finally {
if (!committed) conn.rollback();
}
}
finally {
conn.close();
}
return storedPassword;
}
P.S I want the content of the rows.

I'm hoping I understand what you are asking for, but I fear I don't as it seems too simple, but anyway...
I think you want the contents of 3 columns, not rows. And yes you can, you just specify the columns you want returned in your SQL statement:
SELECT SessionTTL, MAXACTIVEUSERS, ACTIVEUSERS FROM GLOBALSETTINGS WHERE (condition)...
you can also use * as a shortcut for all columns iof you don't want to explicitly specify them:
SELECT * FROM GLOBALSETTINGS WHERE (condition)...
Some background reading on SQL syntax might be useful

If I read this correctly (sorry if mistaken), all you want to do is change your SQL command to select ALL COLUMNS in your database table.
To do so:
string SqlAll = #"SELECT Database.SessionTTL, Database.MAXACTIVEUSERS, Database.ACTIVEUSERS FROM Database";
This will retrieve ALL columns in the database. You can also have conditional statements in your queries when you want to filter for logical reasons, such as TOP 20 to get the first 20 results from the result set.

If you like to return multiple lines with one sql query, you may want to look into ArrayList as you need a loop, where the code would go through your records and match and find all possible results until the end of the records list.

Value from last inserted row in DB [duplicate]

This question already has answers here:
How to get a value from the last inserted row? [duplicate]
(14 answers)
Closed 9 years ago.
Is there some way to get a value from the last inserted row?
I am inserting a row where the PK will automatically increase due to sequence created, and I would like to get this sequence number. Only the PK is guaranteed to be unique in the table.
I am using Java with a JDBC and Oracle.
I forgot to add that I would like to retrieve this value using the resultset below. (I have tried this with mysql and it worked successfully, but I had to switch over to Oracle and now I get a string representation of the ID and not the actually sequence number)
Statement stmt = conn.createStatement();
stmt.executeUpdate(insertCmd, Statement.RETURN_GENERATED_KEYS);
stmt.RETURN_GENERATED_KEYS;
ResultSet rs = stmt.getGeneratedKeys();
if(rs.next()){
log.info("Successful insert");
id = rs.getString(1);
}
The above snippet would return the column int value stored in a mysql table. But since I have switched over to Oracle, the value returned is now a strange string value.

What you're trying to do is take advantage of the RETURNING clause. Let's setup an example table and sequence:
CREATE TABLE "TEST"
( "ID" NUMBER NOT NULL ENABLE,
"NAME" VARCHAR2(100 CHAR) NOT NULL ENABLE,
CONSTRAINT "PK_TEST" PRIMARY KEY ("ID")
);
CREATE SEQUENCE SEQ_TEST;
Now, your Java code should look like this:
String insertSql = "BEGIN INSERT INTO TEST (ID, NAME) VALUES (SEQ_TEST.NEXTVAL(), ?) RETURNING ID INTO ?; END;";
java.sql.CallableStatement stmt = conn.prepareCall(insertSql);
stmt.setString(1, "John Smith");
stmt.registerOutParameter(2, java.sql.Types.VARCHAR);
stmt.execute();
int id = stmt.getInt(2);

This is not consistent with other databases but, when using Oracle, getGeneratedKeys() returns the ROWID for the inserted row when using Statement.RETURN_GENERATEDKEYS. So you need to use the oracle.sql.ROWID proprietary type to "read" it:
Statement stmt = connection.createStatement();
stmt.executeUpdate(insertCmd, Statement.RETURN_GENERATED_KEYS);
ResultSet rs = stmt.getGeneratedKeys();
oracle.sql.ROWID rid = (oracle.sql.ROWID) rs.getObject(1);
But this won't give you the generated ID of the PK. When working with Oracle, you should either use the method executeUpdate(String sql, int[] columnIndexes) or executeUpdate(String sql, String[] columnNames) instead of executeUpdate(String sql, int autoGeneratedKeys) to get the generated sequence value. Something like this (adapt the value to match the index or the name of your primary key column):
stmt.executeUpdate(INSERT_SQL, new int[] {1});
ResultSet rs = stmt.getGeneratedKeys();
Or
stmt.executeUpdate(INSERT_SQL, new String[] {"ID"});
ResultSet rs = stmt.getGeneratedKeys();
While digging a bit more on this, it appears that this approach is shown in the Spring documentation (as mentioned here) so, well, I guess it can't be totally wrong. But, unfortunately, it is not really portable and it may not work on other platforms.

You should use ResultSet#getLong() instead. If in vain, try ResultSet#getRowId() and eventually cast it to oracle.sql.ROWID. If the returned hex string is actually the ID in hexadecimal flavor, then you can try converting it to decimal by Long#valueOf() or Integer#valueOf().
Long id = Long.valueOf(hexId, 16);
That said, Oracle's JDBC driver didn't support ResultSet#getGeneratedKeys() for a long time and is still somewhat troublesome with it. If you can't get that right, then you need to execute a SELECT CURRVAL(sequencename) on the same statement as you did the insert, or a new statement inside the same transaction, if it was a PreparedStatement. Basic example:
public void create(User user) throws SQLException {
Connection connection = null;
PreparedStatement preparedStatement = null;
Statement statement = null;
ResultSet generatedKeys = null;
try {
connection = daoFactory.getConnection();
preparedStatement = connection.prepareStatement(SQL_INSERT);
preparedStatement.setValue(1, user.getName());
// Set more values here.
int affectedRows = preparedStatement.executeUpdate();
if (affectedRows == 0) {
throw new SQLException("Creating user failed, no rows affected.");
}
statement = connection.createStatement();
generatedKeys = statement.executeQuery(SQL_CURRVAL);
if (generatedKeys.next()) {
user.setId(generatedKeys.getLong(1));
} else {
throw new SQLException("Creating user failed, no generated key obtained.");
}
} finally {
close(generatedKeys);
close(statement);
close(preparedStatement);
close(connection);
}
}
Oh, from your code example, the following line
stmt.RETURN_GENERATED_KEYS;
is entirely superfluous. Remove it.
You can find here another example which I posted before about getting the generated keys, it uses the normal getGeneratedKeys() approach.

Return ROWID Parameter from insert statement using JDBC connection to oracle

I can't seem to get the right magic combination to make this work:
OracleDataSource ods = new oracle.jdbc.pool.OracleDataSource();
ods.setURL("jdbc:oracle:thin:app_user/pass#server:1521:sid");
DefaultContext conn = ods.getConnection();
CallableStatement st = conn.prepareCall("INSERT INTO tableA (some_id) VALUES (1) RETURNING ROWID INTO :rowid0");
st.registerReturnParameter(1, OracleTypes.ROWID);
st.execute();
The error I get is "Protocol Violation". If I change to registerOutParameter(), I get notified that I haven't registered all return variables. If I wrap the statement in a PL/SQL begin; end; block then I get the parameter just fine using a regular registerOutParameter() call. I would really prefer to avoid wrapping all my inserts statements in PL/SQL - so what is missing from above?

Usually you don't want to make code database dependent. Instead of OraclePreparedStatement, you should use CallableStatement.
CallableStatement statement = connection.prepareCall("{call INSERT INTO tableA (some_id) VALUES (1) RETURNING ROWID INTO ? }");
statement.registerOutParameter( 1, Types.VARCHAR );
int updateCount = statement.executeUpdate();
if (updateCount > 0) {
return statement.getString(1);
}

A few things you'll need to do
Change CallableStatement to OracleCallableStatement
Try and return into a NUMBER, ie: OracleTypes.Number
Sample code for returning info from a query:
OraclePreparedStatement pstmt = (OraclePreparedStatement)conn.prepareStatement(
"delete from tab1 where age < ? returning name into ?");
pstmt.setInt(1,18);
/** register returned parameter
* in this case the maximum size of name is 100 chars
*/
pstmt.registerReturnParameter(2, OracleTypes.VARCHAR, 100);
// process the DML returning statement
count = pstmt.executeUpdate();
if (count>0)
{
ResultSet rset = pstmt.getReturnResultSet(); //rest is not null and not empty
while(rset.next())
{
String name = rset.getString(1);
...
}
}
More info on Oracle's JDBC extensions:
http://download-uk.oracle.com/docs/cd/B19306_01/java.102/b14355/oraint.htm

Don't know if this applies or not since you don't specify what version you're using.
From Oracle Metalink:
Cause
In the 10.1.0.x JDBC driver, returning DML is not supported:
Per the JDBC FAQ:
"10.1.0 (10g r1)
Is DML Returning Supported ?
Not in the current drivers. However, we do have plans to support it in post 10.1.0 drivers. We
really mean it this time."
As the application code is trying to use unsupported JDBC features, errors are raised.
Solution
Upgrade the JDBC driver to 10.2.0.x, because per the FAQ the 10.2.0.x JDBC drivers do support returning clause:
"10.2.0 (10g r2)
Is DML Returning Supported ?
YES! And it's about time. See the Developer's Guide for details. "
EDIT
Just for grins, you can check the version of JDBC Oracle thinks it's using with:
// Create Oracle DatabaseMetaData object
DatabaseMetaData meta = conn.getMetaData();
// gets driver info:
System.out.println("JDBC driver version is " + meta.getDriverVersion());
If that shows a JDBC driver 10.2.0.x or later, then I'm out of ideas and perhaps a support request to oracle is in order...

PreparedStatement prepareStatement = connection.prepareStatement("insert...",
new String[] { "your_primary_key_column_name" });
prepareStatement.executeUpdate();
ResultSet generatedKeys = prepareStatement.getGeneratedKeys();
if (null != generatedKeys && generatedKeys.next()) {
Long primaryKey = generatedKeys.getLong(1);
}
I have found the answer this is perfectly works. I can insert from JAVA and its return with the key.
Full version:
CREATE TABLE STUDENTS
(
STUDENT_ID NUMBER NOT NULL PRIMARY KEY,
NAME VARCHAR2 (50 BYTE),
EMAIL VARCHAR2 (50 BYTE),
BIRTH_DATE DATE
);
CREATE SEQUENCE STUDENT_SEQ
START WITH 0
MAXVALUE 9999999999999999999999999999
MINVALUE 0;
And the Java code
String QUERY = "INSERT INTO students "+
" VALUES (student_seq.NEXTVAL,"+
" 'Harry', 'harry#hogwarts.edu', '31-July-1980')";
// load oracle driver
Class.forName("oracle.jdbc.driver.OracleDriver");
// get database connection from connection string
Connection connection = DriverManager.getConnection(
"jdbc:oracle:thin:#localhost:1521:sample", "scott", "tiger");
// prepare statement to execute insert query
// note the 2nd argument passed to prepareStatement() method
// pass name of primary key column, in this case student_id is
// generated from sequence
PreparedStatement ps = connection.prepareStatement(QUERY,
new String[] { "student_id" });
// local variable to hold auto generated student id
Long studentId = null;
// execute the insert statement, if success get the primary key value
if (ps.executeUpdate() > 0) {
// getGeneratedKeys() returns result set of keys that were auto
// generated
// in our case student_id column
ResultSet generatedKeys = ps.getGeneratedKeys();
// if resultset has data, get the primary key value
// of last inserted record
if (null != generatedKeys && generatedKeys.next()) {
// voila! we got student id which was generated from sequence
studentId = generatedKeys.getLong(1);
}
}
source : http://viralpatel.net/blogs/oracle-java-jdbc-get-primary-key-insert-sql/

Try using ? instead of :rowid0 on your SQL string. I have had problems before with named parameters and Oracle.