prepared-statement

I am using JDBC connection object obtained from hibernate to perform bath update, I am doing this because I need to use the MySql ON DUPLICATE feature. But, when trying to insert I am not able to inset saying the string has special characters, Session session = sessionFactory.openSession(); PreparedStatement pstm = null; Connection conn = session.connection(); try { IRKeyWordTweet record = null; conn.setAutoCommit(false); for (Iterator itrList = statusToInsert.iterator(); itrList.hasNext();) { try { record = (IRKeyWordTweet) itrList.next(); pstm = (PreparedStatement) conn.prepareStatement(

I'm trying to run multiple queries on my database using MySQLi. This is my code: $stmt = $mysqli->prepare('SELECT password FROM `users` WHERE username=? LIMIT 1'); $stmt->bind_param('s', $username); $stmt->execute(); $stmt->bind_result($hashedPass); $stmt->fetch(); /* Check the passwords match */ $pwdHasher = new PasswordHash(8, FALSE); if(!$pwdHasher->CheckPassword($password, $hashedPass)) exit; $stmt = $mysqli->prepare('SELECT u_id FROM `users` WHERE username=? LIMIT 1'); $stmt->bind_param('s', $username); $stmt->execute(); $stmt->bind_result($u_id); $stmt->fetch(); But when the code is run

I am looking for a way to achieve PreparedStatement caching, so as to save recreating the PreparedStatement objects for queries that were already executed in the past. Is there some built in way to achieve this using Tomcat? Or must I program this cache myself? I believe tomcat uses commons-dbcp and commons-dbcp supports prepared statement pooling. check it out here . poolPreparedStatements false Enable prepared statement pooling for this pool. Prepared statement caching is done by either your JDBC connection pool or your JDBC driver, not by Tomcat. You don't state your database, but if it's

What is the importance of using: $stmt->free_result(); $stmt->close(); After a database call using prepared statments like this: $mysqli=new mysqli("database", "db", "pass", "user"); $stmt = $mysqli->prepare("SELECT email FROM users WHERE id=? "); $stmt->bind_param('i',$_SESSION['id']); $stmt->execute(); $stmt->bind_result($email); while($stmt->fetch()){ echo $email; } $stmt->free_result(); //why do i need this? $stmt->close(); //why do i need this? Im asking because I do not see any noticeable performance degradation without them. Are those commands usually only used for when I store the

I have a query that updates a record on my database, it works fine but i wanted to know how to check if the update has happened so i can return true and display the right message? Now i know with a SELECT query i can do: if(stmt->fetch()) If that is true i return true and saying "records found" but i haven't got a clue how to do it for an update query? Anyone know how to? $query = "UPDATE user SET password = ? WHERE email = ?"; if($stmt = $conn->prepare($query)) { $stmt->bind_param('ss', $pwd, $userEmail); $stmt->execute(); //Check if update worked } Thanks for the help. Fahim Parkar check if

I was using so far something like this for querying my database that was working perfectly fine : PreparedStatement prepStmt = dbCon.prepareStatement(mySql); ResultSet rs = prepStmt.executeQuery(); But then I needed to use the rs.first(); in order to be able to iterate over my rs multiple times. So I use now PreparedStatement prepStmt = dbCon.prepareStatement(mySql,ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE); My question is related to the performance of the two. What do I lose if I use the second option? Will using the second option have any negative effect in the code that

I have the below questions on Prepared Statements in Java. Is it beneficial to use Prepared Statements when the SQL Query does not have any Where clause ? Assume a simple query Select * from tablename; It is said that the Prepared Statement is compiled once and only the values are substituted the second time. Hence it is faster as the Query validation and compilation step can be skipped. Where is the compiled form stored ? What is the life time of this compiled form ? A PreparedStatement is beneficial when there are parameters to be passed and when the query is to be executed repeatedly. If

I do understand that the prepared statements is the ultimate way to seek protection against the SQL injection. However, they provide coverage in a limited fashion; for example, in cases where I let the user to decide how the order by operation to be ( i.e, is it ASC or DESC? etc ), I get no coverage there with the prepared statements. I understand that I can map the user input to a pre-defined white list for that. But, this is only possible when a whitelist can be created or guessed thoroughly beforehand. For example, in the cases I mention above ( the ASC, or DESC ), this can easily be mapped