![]() ![]() SQL Server 2014's Memory-Optimized Tables and Transaction Retry Rerun the transaction."īut transaction retry logic isn't limited to correcting deadlocks there are several other circumstances in which you may want to retry a failed transaction like server timeouts, errors due to concurrent schema modification operations and so on. Although you can set deadlock priority for each transaction by using SET DEADLOCK_PRIORITY option, one of them will be killed and you will get this error 1205: "Transaction (Process ID %d) was deadlocked on %.*ls resources with another process and has been chosen as the deadlock victim. That's where deadlocks come to light.Ī deadlock happens when two or more tasks block each other because each task has a lock on a resource that the other task(s) are trying to lock. To keep consistency, concurrent transactions must be independent of each other (Isolation) and changes must persist (Durability).Īlthough this makes database systems reliable in most circumstances, following these properties is difficult and drastic measures are sometimes taken by SQL Server or any other RDBMS. SQL Server cannot commit half a transaction because doing so will violate the second principle (Consistency). A transaction must be either committed or rolled back entirely (Atomicity). The following code snippet shows you how to retrieve and process a result set returned from a stored procedure using JDBC code: CallableStatement statement = conn.We all know that every RDBMS system has to guarantee the ACID principle (Atomicity, Consistency, Isolation and Durability). Consider the following procedure: CREATE PROCEDURE `get_books`(IN rate INT)ĮNDLet’s see how to retrieve this result set in Java. Calling a Stored Procedure Returning a Result Set from JavaA stored procedure can returns a result set. Notice that the variable newAuthorID is used in the second INSERT statement to set foreign key for the new row.Within the workbench, you can call this stored procedure by executing the following query:Ĭall create_author('Patrick Maka', let’s see how to call this stored procedure using JDBC.Here are the steps to call a simple stored procedure from Java code with JDBC: CallableStatement statement = connection.prepareCall("Running this program would give the following output:Ĥ. ![]() Then we insert a new row into the table book, in which we use the author name for the title and description of the book. Then select the ID value of this recently inserted row ( author_id), store it into a variable named newAuthorID. It has two input parameters name and email.In the body of the procedure (code between BEGIN and END), we insert a row into the table author. ![]() INSERT INTO book (title, description, published, author_id, price, rating)Īs you can see, this stored procedure is named as create_author. SET newAuthorID = (SELECT author_id FROM author a WHERE a.name = name) INSERT INTO author (name, email) VALUES (name, email) Right click and select Create Routine…) and paste the following code: CREATE PROCEDURE `booksdb`.`create_author` (IN name VARCHAR(45), email VARCHAR(45)) Calling a Simple Stored Procedure from JavaIn MySQL Workbench, create a new routine (expand the database and you see a node called Routines. Here’s the database structure: Imagine we have some dummy data for the table author as following: And dummy data for the table book as following: 1. We will use MySQL database for the examples, and suppose that you know how to create a stored procedure using MySQL Workbench tool. Calling a stored procedure which returns a result set and process this result set.Calling a stored procedure which has IN, OUT and INOUT parameters and retrieve the values of these parameters.Calling a simple stored procedure which has only IN parameters.This Java tutorial provides various examples that help you understand how to work with stored procedure using JDBC. ![]()
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