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Error in SQL syntax when running SQL in Java but not in HeidiSQL

I'm trying to run an insert or update on a table - the string generated from below works fine when copy pasted into HeidiSQL but throws SQLSyntaxErrorExceptions when run from Java:
Statement statement = con.createStatement();
String escapedXML = EscapeString(billboard.getXml());
String sql = String.format(
"DELIMITER $ \r\nBEGIN NOT ATOMIC\r\n" +
"IF EXISTS(SELECT * FROM billboards where Name='%s') THEN UPDATE billboards SET XML='%s' where Name='%s';\r\n" +
"ELSE insert into billboards(Name, XML, CreatorName) values('%s', '%s', '%s');\r\n" +
"END IF;\r\n" +
"END $\r\n" +
"DELIMITER ;", billboard.getName(), escapedXML, billboard.getName(), billboard.getName(), escapedXML, billboard.getCreatorName());
// Insert or update billboard
statement.execute(sql);
I can't figure out why.

I would recommend using the insert ... ok duplicate key syntax here rather than a code block. This is more efficient, and implements the lockout a single statement, which should avoid the problem you meet when running the query from your php code.
insert into billboards(Name, XML, CreatorName)
values(?, ?, ?)
on duplicate key update set XML = values(XML)
For this to work, you need a unique (or primary key) constraint on column Name.
Also, consider using a parameterized query rather than concatenating variables in your query stringW Escaping is inefficient and does not really make your code safer.

You should have tried NamedParameterStatement with your query to facilitate setting of string parameters and avoid their duplication (using refactored query suggested in GMB's earlier answer):
String sql = "INSERT INTO billboards (Name, XML, CreatorName) VALUES (:name, :xml, :creator) "
+ "ON DUPLICATE KEY UPDATE SET XML = :xml";
NamedParameterStatement statement = new NamedParameterStatement(con, sql);
statement.setString("name", billboard.getName());
statement.setString("xml", EscapeString(billboard.getXml()));
statement.setString("creator", billboard.getCreatorName());
// Insert or update billboard
statement.execute(sql);

The reason that you are getting a syntax error is that DELIMITER is a MySQL client command and not an SQL statement. MySQL commands may not be used in with JDBC.
For more information:
Delimiters in MySQL

Java prepared statement throwing SQLIntegrityConstraintViolationException: Invalid argument(s) in call

I am trying to insert a record into DB (Oracle) through Java code. When it is preparing statement at that time it is throwing an exception
java.sql.SQLIntegrityConstraintViolationException: Invalid argument(s) in call
on below line of code:
PreparedStatement ps = connection.prepareStatement(INSERT_QUERY);
and the insert query is:
private static final String INSERT_QUERY = "INSERT INTO ABC ( uid,created_datetime,status,update_datetime,b_id,ref_no,ref_dt,sor,b1_id,c_code,base,name,src,trn_date,country,pr,cv,features,scoring_time_ms,scoring_request_time_ms,preprocessing_time_ms,postprocessing_time_ms,overall_time_ms )VALUES ( ?,current_timestamp,?,current_timestamp,?,?,?,?,?,?,?,?,?,current_timestamp,?,?,?,?,?,?,?,?,? )";
When I debugged the code I found that when it is preparing statement connection.prepareStatement(INSERT_QUERY); insert query is showing as below:
INSERT INTO ABC ( uid,created_datetime,status,update_datetime,b_id,ref_no,ref_dt,sor,b1_id,c_code,base,name,src,trn_date,country,pr,cv,features,scoring_time_ms,scoring_request_time_ms,preprocessing_time_ms,postprocessing_time_ms,overall_time_ms )VALUES ( ?,systimestamp,?,systimestamp,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,? )
It is changing current_timestamp to systimestamp and also I have 3 current_timestamp in the query and it is missing 3rd one while debugging.
I have deleted all the records from database. DB is empty and it has no constraints, only primary key.
Can anyone help me on this issue. Why is this happening and how can I resolve this?

SQLIntegrityConstraintViolationException points to a db constraint violation. Check the for primary/unique/foreign keys in the table "ABC". Just based on the insert statement, can assume uid must be unique.

This issue is resolved. It was build issue. It was not taking updated code so getting that error. Deleted everything from .m2 dir and build it again and this error got disappeared.

Mysql Duplicate entry 'xxxxxxxx' for key(unique) 'xxxxxxxxxx'

I have a problem of updating a row. I have a column called serialNum with varchar(50) not null unique default null
When I get the response data from the partner company, i will update the row according to the unique serial_num (our company's serial num).
Sometimes update failed because of :
Duplicate entry 'xxxxxxxx' for key 'serialNum'
But the value to update is not exists when i search the whole table. It happens sometimes, not always, like about 10 times out of 300.
Why does this happen and how can I solve it?
below is the query i use to update:
String updateQuery = "update phone set serialNum=?, Order_state=?, Balance=? where Serial_num=" + resultSet.get("jno_cli");
PreparedStatement presta = con.prepareStatement(updateQuery);
presta.setString(1, resultSet.get("oid_goodsorder"));
presta.setString(2, "order success");
presta.setFloat(3, Float.valueOf(resultSet.get("leftmoney")));
presta.executeUpdate();

I think the reason is in resultSet.get("oid_goodsorder") where did you get this result? is 'oid_goodsorder' is unique? Did you always updates whole table?
If oid_goodsorder is unique, it is possible to have duplicates in serialNum, because you don't use bulk update, instead you update every record separately, therefore it is possible:
Before:
serialNum=11,22,33,44
oid_goodsorder=44,11,22,33
It tries to update first serialNum to 44, but 44 is exists!
But if you finish all update serialNum will be unique...
If you wants to get error rows you could disable set serialNum is not unique and check table for duplicating serialNum
If you don't have duplicating values try to use bulk update
Java - how to batch database inserts and updates

How can I avoid entering duplicate entries in my MySQL database?

So, what I'm trying to do here is check the user table in my users mySQL database for duplicate entries in the username row, before inserting a new username. Here's an example of my code. Currently, the results ResultSet does not do anything and I'm not exactly sure how to implement it into the IF statement that follows. And yes, I have the catches for the try, just not in this example. Sorry if this is a rather simple question, I just started programming with Java last week. Also, it's my first question on here and I definitely appreciate the help.
try{
String sequel = ("SELECT username FROM `users`.`user`");
PreparedStatement userNameInfo = conn.prepareStatement(sequel);
userNameInfo.executeQuery(sequel);
ResultSet results = userNameInfo.getResultSet();
if (sequel.equals("")) {
conn.setAutoCommit(false);
String sql = "INSERT INTO `users`.`user`(`username`,`password`,`email`) VALUES('" + newusername +"', '" + newpassword + "', '" + newemail +"')";
PreparedStatement prest = conn.prepareStatement(sql);
prest.executeUpdate(sql);
conn.commit();
conn.close();
System.out.println("Added Successfully!");
}
else {
System.out.println("Add failed!");
}
}

So I think what you trying to do - and should do I think, is select if the username is in the table then add or not. So the sql needs to be like:
select username from users where username = ?
then set the param in the query. See docs here:
http://docs.oracle.com/javase/6/docs/api/java/sql/PreparedStatement.html
You then need to check what is in the resultset after the query, and see if anything is in there. The API docs for this will be in about the same place as the PreparedStatement docs.
Adding a constraint in the db will also give you a belt and braces.
Hope this helps

When you define your SQL table, you can define some items to be unique.
So in your example, if you want usernames to be unique, you would add:
UNIQUE(username)
to your table declaration.
If you want the pair username / email to be unique, you would add:
UNIQUE(username, email)
The documentation is here

Have you created the primary key in the table? A primary key automatically prevents duplicate values.
If you want to prevent duplicate usernames, then make your username column the primary key.

Umm, I am not a java guy. But this may help you.
You can retrieve the row count of the first result set after the query executes. If the row count is equal to 0, that means database does not contain a similar record.

remove duplicate values while insertion

Hi I am trying to insert values from excel sheet into SQL Database in java. SQL database has already some rows inserted by some other techniques. Now I need to insert new rows from excel sheet and should eliminate the duplicate values which are existed in the database as well as in the excel sheet. For that I write a query like this.
First I inserted the records from excelsheet into SQL database by using insert query
Statement.executeUpdate(("INSERT INTO dbo.Company(CName,DateTimeCreated) values
('"+Cname”' ,'"+ts+"');
Later I deleted the duplicate values using delete query.
String comprows="delete from dbo.Company where Id not in"
+ "(select min(Id) from dbo.Company "
+ "group by CName having count(*)>=1)";
statement3.executeUpdate(comprows);
where Id is autoincremented integer.
but it is not good to do insert and then delete.
How do I know the values are already exist? If it is exist how do I remove during insertion???

You can simply fire a SELECT for the CName first. If a record is found, update else insert a new record.
Edited to add code snippet:
ResultSet rs = Statement.query("SELECT Id from dbo.Company where CNAME = '" +Cname + "'");
if(rs.next()) {
// retrieve ID from rs
// fire an update for this ID
} else {
// insert a new record.
}
Alternatively, if you think that there are already duplicates on your table and you want to remove them as well..
ResultSet rs = Statement.query("SELECT Id from dbo.Company where CNAME = '"+Cname + "'");
List idList = new ArrayList();
while(rs.next()) {
// collect IDs from rs in a collection say idList
}
if(!isList.isempty()) {
//convert the list to a comma seperated string say idsStr
Statement.executeUpdate("DELETE FROM dbo.Company where id in ("+ idsStr + ")");
}
// insert a new record.
Statement.executeUpdate(("INSERT INTO dbo.Company(CName,DateTimeCreated) values('"+Cname”' ,'"+ts+"');
Of course good practice is to use PreparedStatement as it would improve performance.
PS: Excuse me for any syntax errors.

One option would be to create a temp table and dump your Excel data there. Then you can write an insert that joins the temp table with the dbo.Company table and only insert the records that aren't already there.
You could do a lookup on each record you want to insert but if you are dealing with large volumes that's not a super efficient way to do it since you will have to do a select and an insert for each record in you excel spreadsheet.
Merge statements are pretty effective in these types of situations as well. I don't think all databases support them (I know Oracle does for sure). A merge statement is basically a combo insert and update so you can do the look up to the final table and insert if not found and update if found. The nice thing about this is you get the efficiency of doing all of this as a set rather than one record at a time.

If you can control the DB schema, you might consider putting a unique contraint for whatever column(s) to avoid duplicating. When you do your inserts, it'll throw when it tries to add the dup data. Catch it before it tosses you all the way out.
It's usually good to enforce constraints like this on the DB itself; that means no one querying the database has to worry about invalid duplicates. Also, optimistically trying the insert first (without doing a separate select first) might be faster.