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java.sql.SQLSyntaxErrorException when inserting into MySQL database using PreparedStatement [duplicate]

I'm trying to execute a query using a PreparedStatement in Java.
I am getting error number 1064 when I try to execute my query (syntax error).
I have tested this in MySQL query browser with substituted values which works fine.
What's wrong with my code?
Here's the relevant code:
String query = "select MemberID, MemberName from members where MemberID = ? or MemberName = ?";
Connection conn = DriverManager.getConnection(DATABASE_URL, USERNAME, PASSWORD);
PreparedStatement s = conn.prepareStatement(query);
s.setInt(1, 2);
s.setString(2, "zen");
ResultSet rs = s.executeQuery(query);
Here's the exception I'm getting:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an
error in your SQL syntax; check the manual that corresponds to your
MySQL server version for the right syntax to use near '? or MemberName
= ?' at line 1

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '? or MemberName = ?' at line 1
MySQL doesn't understand the meaning of ? in the SQL query. It's indeed invalid SQL syntax. So somehow it's not been replaced by PreparedStatement. And guess what?
PreparedStatement s = conn.prepareStatement(query);
s.setInt(1, intValue);
s.setString(2, strValue);
rs = s.executeQuery(query); // Fail!
You're overridding the prepared query with the original query! You need to call the argumentless PreparedStatement#executeQuery() method instead of Statement#executeQuery(String).
PreparedStatement s = conn.prepareStatement(query);
s.setInt(1, intValue);
s.setString(2, strValue);
rs = s.executeQuery(); // OK!
Unrelated to the problem, your code is leaking resources. The DB will run out of them after several hours and your application will crash. To fix this, you need to follow the JDBC idiom of closing Connection, Statement and ResultSet in the finally block of the try block where they're been acquired. Check the JDBC basic tutorial for more detail.

If you look at the javadocs for Statement (the superclass of PreparedStatement), the method docs for executeQuery(String) and executeUpdate(String) say this:
Note: This method cannot be called on a PreparedStatement or CallableStatement.
That's what you are doing here: calling executeQuery(String) from Statement on a PreparedStatement object.
Now since the javadocs say that you "cannot" do this, actual behavior you get is unspecified ... and probably JDBC driver dependent. In this case, it appears that the MySQL driver you are using is interpreting this to mean that you are doing the update as a non-prepared statement, so that the ? tokens are NOT interpreted as parameter placeholder. That leads the server-side SQL parser to say "syntax error".
(It would be easier for programmers if a different unchecked exception was thrown by the MySQL driver if you did this; for example UnsupportedOperationException. However, the standard JDBC javadocs don't say what should happen in this situation. It is up to the vendor what their drivers will do.)

MySQL Syntax error | You have an error in your SQL syntax;

Error:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'lock WHERE player='SrLolok'' at line 1
Code:
PreparedStatement search = instance.getConnection().prepareStatement("SELECT * FROM lock WHERE player=?;");
search.setString(1, player);
ResultSet rs = search.executeQuery();

lock is a reserved word in MySQL.
If you want to use it, you need to surround it with backticks:
SELECT * FROM `lock` WHERE player=?
Or better yet, use a table name that does not correspond to a reserved word, so you don't need to worry about this.

Strange behaviour of Java PreparedStatement

I have the following code
try{
sql = "Select Time, Text WHERE Sender =?";
PreparedStatement stmt = conn.prepareStatement(sql);
stmt.setString(1, "ABC");
rs = stmt.executeQuery();
}catch(SQLException){
System.out.println(e.getMessage());
}
And get the following error:
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'WHERE Sender ='ABC'' at line 1
There is an extra ' in my SQL query, how can I fix that?

It's not the "extra" ' that's the issue. You actually need that for your DB to understand the text you're providing.
The issue is that you're issuing a SELECT statement that is requesting fields from a table which you have not specified. You need to add the table name:
Select Time, Text FROM <tablename here> WHERE Sender =?
Edit: Apparently MariaDB doesn't consider time and text as reserved words as #Andreas pointed out in a comment on this answer.

Delete column from database

I have a database with so many values.How can i delete a specified row using a query.
I am using following query for deletion.I want to delete a row whith the help of colum name=user_name.(user_name=example).
But example named row is not present at the table.is shows error.Any if exist query for this
preparedStatement = (PreparedStatement) connection.prepareStatement("DELETE FROM users WHERE IF EXISTS user_name=example");
preparedStatement.executeUpdate();
The following error occur when i trying to compile
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'EXISTS user_name='example'' at line 1

remove IF EXISTS
use user_name='example' (with quotes) or even better user_name=? with PreparedStatement
use preparedStatement.executeUpdate()
it shouldnt throw any error even if no result

I think you just forgot the apostrophs that span the String literal 'example':
DELETE FROM users WHERE user_name='example'.
The 'WHERE EXISTS' is unnecessary here!
Greetings
Christopher

I tried here in my computer this way and works fine
PreparedStatement pt =con.prepareStatement("DELETE FROM users WHERE IF EXISTS user_name='"+"example'");
pt.executeUpdate();
I made a temporary table and run it

Scrollable ResultSet JDBC Postgresql

When I create a prepared statement like this in java (using JDBC):
pStmt = conn.prepareStatement(qry);
everything works ok. However when I want a scrollable resultset and use this:
pStmt = conn.prepareStatement(qry,ResultSet.TYPE_SCROLL_INSENSITIVE);
I get a syntax error:
org.postgresql.util.PSQLException: ERROR: syntax error at or near "RETURNING"
I'm not even using RETURNING in my query.
Any ideas?
Any help would be appreciated. Thanks
Update:
It seems to work if I use this:
pStmt = db.prepareStatement(qry,ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
What is the difference between SENSITIVE and INSENSITIVE?
Thanks

The second parameter to prepareStatement should be one of Statement.RETURN_GENERATED_KEYS or Statement.NO_GENERATED_KEYS.
I guess you want to use
PreparedStatement prepareStatement(String sql,
int resultSetType,
int resultSetConcurrency)

ResultSet.TYPE_SCROLL_INSENSITIVE : This assumes that the result set does not “sense” database changes that occurred after execution of the query.
ResultSet.TYPE_SCROLL_SENSITIVE : picks up changes in the database that occurred after execution of the query