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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

Mysql -Issue with preparedStatement insert query

I have a table in a MySQL database which is 2 columns,
String insertquery = "INSERT INTO Table (Col1, Col2) VALUES (?, ?)";
PreparedStatement preparedStatement = dbConnection.prepareStatement(insertSQL);
preparedStatement.setString(1, "Val 1");
preparedStatement.setString(2, "Val 2");
preparedStatement.executeUpdate();
The thing is that the second column values decide at run time, where to insert value or keep default.
how to set setString as default .
preparedStatement.setString(2, default );
or can i write two seperate sql depends upon condition ? is there any way to handle this senario?
same issue for update sql.
String updatequery = "UPDATE Table SET Col1=?, Col2=?;"
PreparedStatement preparedStatement = dbConnection.prepareStatement(updatequery);
preparedStatement.setString(1, "Val 1");
preparedStatement.setString(2, "Val 2");
preparedStatement.executeUpdate();
I am able to set like this
preparedStatement.setNull(2, '');
I have to kept old value as it is, not update as null
Thank you...

To achieve this, you have to leave out the column name and MySQL will then use the default value for any column names that have been omitted.
So when you want the value of Col2 to be the default, then you would write your query like so:
"INSERT INTO Table (Col1) VALUES (?)";
I think your best choice is to actually prepare the statement itself at run-time based on the columns that you want to change.
I'm not really sure how easily this can be done in Java but with PHP this could be done so easily by having an array of column names and adding/removing items off the array at run-time depending on what columns needs to be updated and then using the PHP Implode function to glue each item of the array with a comma and finally concatenating the resulting string to your final query.
Maybe you might be able to find solutions that are more suited for java by reading through this related stack-overflow answer.
Good luck

Inserting variables with SQL in Java

I'm writing a webpage that takes input from a form, sends it through cgi to a java file, inserts the input into a database through sql and then prints out the database. I'm having trouble inserting into the database using variables though, and I was wondering if anyone would be able to help me out.
String a1Insert = (String)form.get("a1");
String a2Insert = (String)form.get("a2");
This is where I get my variables form the form (just believe that it works, there's a bunch more back end but I've used this before and I know it's getting the variables correctly).
String dbURL = "jdbc:derby://blah.blahblah.ca:CSE2014;user=blah;password=blarg";
Connection conn = DriverManager.getConnection(dbURL);
Statement stmt = conn.createStatement();
stmt.executeUpdate("set schema course");
stmt.executeUpdate("INSERT INTO MEMBER VALUES (a1Insert, a2Insert)");
stmt.close();
This is where I try to insert into the databse. It give me the error:
Column 'A1INSERT' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE statement then 'A1INSERT' is not a column in the target table.
If anyone has any ideas that would be lovely ^.^ Thanks

java.sql.Statement doesn't support parameters, switching to java.sql.PreparedStatement will allow you to set parameters. Replace the parameter names in your SQL with ?, and call the setter methods on the prepared statement to assign a value to each parameter. This will look something like
String sql = "INSERT INTO MEMBER VALUES (?, ?)";
PreparedStatement stmt = con.prepareStatement(sql);
stmt.setString(1, "a1");
stmt.setString(2, "a2");
stmt.executeUpdate();
That will execute the SQL
INSERT INTO MEMBER VALUES ('a1', 'a2')
Notice the parameter indexes start from 1, not 0. Also notice I didn't have to put quotes on the strings, the PreparedStatement did it for me.
Alternatively you could keep using Statement and create your SQL string in Java code, but that introduces the possibility of SQL injection attacks. Using PreparedStatement to set parameters avoids that issue by taking care of handling quotes for you; if it finds a quote in the parameter value it will escape it, so that it will not affect the SQL statement it is included in.
Oracle has a tutorial here.

String formatting prob for making database value inside a file

I have a bean class which does maintain user data:
soppose I have created a postgresql DB table like this:
StringBuffer sqlStr = new StringBuffer();
sqlStr.append("CREATE TABLE Users ("
user_id bigint,
username character varying NOT NULL,
biography character varying NOT NULL
);
& I want to make a query command and inject my String data inside it:
sqlStr.append("INSERT INTO users(" +
"user_id, username, biography)" +
"\n\tVALUES (" + user.getID()+ "," + user.getUsername() + "," + user.getBiography()+");";
my problem is for example if the data coming from my method has quote or double quote or "," my command will become wrong suppose that the user biography is something like this :
hello, I'm Mr X an "IT Pro" ...
If I run my application and save the output inside a file called query.sql I can't use it because my query command is wrong because of quote & double quote, something like this:
INSERT INTO users(userid, username, biography)
VALUES(2, 'Mehdi', 'hello, I'm Mr X an "IT Pro" ..');
how Can I fix this problem ?

You should never ever use the above method for constructing SQL queries.
"Why not?" you ask, well; where to start. The classic example is Bobby Tables, the more general problem is SQL injection. This leaves your program open to attack but also to random failure - like the situation you describe.
Now, the solution. Always use PreparedStatement to construct your query. In your example
final String query = "INSERT INTO users(user_id, username, biography) VALUES (?,?,?)";
final PreparedStatement ps = con.prepareStatement(query);
ps.setInt(1, user.getID());
ps.setString(2, user.getUsername());
ps.setString(3, user.getBiography());
ps.executeUpdate();
A much nicer syntax to use with is the the SET syntax rather than the traditional VALUES syntax. The query would then look like
final String query = "INSERT INTO users SET user_id = ?, username = ?, biography = ?";
EDIT
The OP is building a query for a script file, not executing a query in the code.
There is a utility class in Apache Commons Lang, StringEscapeUtils. This has an escapeSql method. Looking at the source code, all this does is escape single quotes with another single quote.
This works if you build your queries with single quotes:
VALUES (" + user.getID()+ ",'" + user.getUsername() + "'...
So the query, once the example value is inserted will go from:
VALUES (10 ,'hello, I'm Mr X an "IT Pro"'...
Will become
VALUES (10 ,'hello, I''m Mr X an "IT Pro"'...
The apostrophe in "I'm" is now escaped and harmless.
Note that you obviously need to escape the values and not the query, so (assuming you have a static import for the class)
VALUES (" + user.getID()+ ",'" + escapeSql(user.getUsername()) + "'...
But does not escape other sql characters, percent signs for example.
This is really a stop-gap measure to make the code work while you come up with a more robust solution. And you should come up with a more robust solution.

Why dont you use PreparedStatement? That will also give you better performance as the SQL will be pre-compiled on DB side.
Or
You can escape the quotes using
String.replaceAll http://docs.oracle.com/javase/6/docs/api/java/lang/String.html#replaceAll(java.lang.String, java.lang.String)

Variable column names using prepared statements

I was wondering if there was any way to specify returned column names using prepared statements.
I am using MySQL and Java.
When I try it:
String columnNames="d,e,f"; //Actually from the user...
String name = "some_table"; //From user...
String query = "SELECT a,b,c,? FROM " + name + " WHERE d=?";//...
stmt = conn.prepareStatement(query);
stmt.setString(1, columnNames);
stmt.setString(2, "x");
I get this type of statement (printing right before execution).
SELECT a,b,c,'d,e,f' FROM some_table WHERE d='x'
I would, however, like to see:
SELECT a,b,c,d,e,f FROM some_table WHERE d='x'
I know that I cannot do this for table names, as discussed
here, but was wondering if there was some way to do it for column names.
If there is not, then I will just have to try and make sure that I sanitize the input so it doesn't lead to SQL injection vulnerabilities.

This indicates a bad DB design. The user shouldn't need to know about the column names. Create a real DB column which holds those "column names" and store the data along it instead.
And any way, no, you cannot set column names as PreparedStatement values. You can only set column values as PreparedStatement values
If you'd like to continue in this direction, you need to sanitize the column names (to avoid SQL Injection) and concatenate/build the SQL string yourself. Quote the separate column names and use String#replace() to escape the same quote inside the column name.

Prepare a whitelist of allowed column names. Use the 'query' to look up in the whitelist to see if the column name is there. If not, reject the query.

For MySQL prepared statements with NodeJS (mysqljs/mysql), what you need to know is that ? is for values, but if you need to escape column names, table names etc, use ?? instead.
Something like this will work:
SELECT ??, ??, ?? FROM ?? WHERE ?? < ?
Set values to ['id', 'name', 'address', 'user', 'id', 100]

I think this case can't work because the whole point of the prepared statement is to prevent the user from putting in unescaped query bits - so you're always going to have the text quoted or escaped.
You'll need to sanitize this input in Java if you want to affect the query structure safely.

Use sql injection disadvantage of Statement Interface as advantage.
Ex:
st=conn.createStatement();
String columnName="name";
rs=st.executeQuery("select "+ columnName+" from ad_org ");

public void MethodName(String strFieldName1, String strFieldName2, String strTableName)
{
//Code to connect with database
String strSQLQuery=String.format("select %s, %s from %s", strFieldName, strFieldName2, strTableName);
st=conn.createStatement();
rs=st.executeQuery(strSQLQuery);
//rest code
}

Below is the solution in java.
String strSelectString = String.format("select %s, %s from %s", strFieldName, strFieldName2, strTableName);