Hello Everyone, I have a SQL report which pulls a list of orders.It returns each product on a new row, so orders with multiple products have multiple rows, 5.The Bakers Dozen 26 Productivity Tips for Optimizing SQL Server Queries Part 1 of 2 By Kevin S Goff.Databases can be toughsometimes the smallest change has the biggest impact.Learn the benefits of tuning and how to optimize your SQL database, from the codebase.ZaiKi.png' alt='Sql Update Millions Of Rows' title='Sql Update Millions Of Rows' />Best practices to improve performance in JDBC Best practices to improve performance in JDBCThis topic illustrates the best practices to improve performance in JDBC with.JDBC defines how a Java program.This section focuses mainly on JDBC 2.API. JDBC API provides two packages.By. using JDBC API, you can connect virtually any database, send SQL queries.JDBC architecture defines different layers to work with any database and java, they.JDBC API interfaces and classes which are at top most layer to work with.JDBC API. interfaces that maps java to database specific language and a database which is at.The following figure illustrates the JDBC architecture.JDBC API provides interfaces and classes to work with databases.Connection interface encapsulates database connection functionality.Statement interface encapsulates SQL query representation and execution.Result. Set interface encapsulates retrieving data which comes from execution of SQL.Statement. The following are the basic steps to write a JDBC program 1.Import java. sql and javax.Load JDBC driver 3.Establish connection to the.Connection interface 4. Single Issue Request Fills Week 42 In 2017 . Create a Statement by passing SQL.Execute the Statement 6.Retrieve results by using.Result. Set interface 7.Close Statement and Connection.We will look at these areas one by one, what type of driver you.Connection interface in the best manner, how to use.Statement interfaces, how to process results using Result.Set and. optimize SQL queries to improve JDBC performance.Note. 1 Your JDBC.JDBC 2. 0 features in order to use some of.Note. 2 This Section assumes that reader has.JDBC. Here we will walk through initially about the types of drivers, availability.Driver is the key player in a JDBC application, it acts as a mediator between.Java application and database.It implements JDBC API interfaces for a database, for example Oracle driver for oracle database, Sybase.Sybase database. It maps Java language to database specific language including SQL.JDBC defines four types of drivers to work with.Depending on your requirement.Here is a brief description of each type of driver Type of driver.Tier. Driver mechanism.Description. 1Two.JDBC ODBCThis driver converts JDBC calls to ODBC calls through JDBC ODBC.Bridge driver which in turn.Client requires ODBC libraries.Two. Native API Partly Java driver.This driver converts JDBC calls to database specific native.Client requires database specific libraries.Three. JDBC Net All Java driver.This driver passes calls to proxy server through network.Client doesnt require any driver.Two. Native protocol All Java driver.This driver directly calls database.Client doesnt require.Obviously the choice of choosing a driver depends on.Generally all the databases support their own drivers or from third.If you dont have driver for your database, JDBC ODBC driver is.ODBC. If you have tiered requirement two tier or three tier for your application.Type three driver between client and proxy server.If you want to connect to database from java applet, then you have.Type four driver because it is only the driver which supports that feature.This figure shows the overall picture of drivers from tiered perspective.This figure illustrates the drivers that can be used for two tiered and three.For both two and three tiered applications, you can filter down.Type three driver but you can use Type one, two and four drivers for both tiered.To be more precise, for java applications non applet you can use Type.Here is exactly where you may make a mistake by.Let us look at. that perspective in the following section.Type 3 4 drivers are faster than other drivers because Type 3 gives facility.Type 4 driver need not translate.ODBC or native connectivity interface.Type 1 drivers are slow because they have to convert JDBC calls to ODBC through JDBC ODBC.Bridge driver initially and then ODBC Driver converts them into database specific.Type 2 drivers give average performance when compared to Type 3 4.Type 2 drivers give better performance than Type 1 drivers.Finally, to improve performance 1.Use Type 4 driver for applet to database communication.Use Type 2 driver for two tiered applications for communication between java.Type. 1 driver. 3.Use Type 1 driver if your database doesnt support a driver.This is rare situation because almost.Use Type 3 driver to communicate between client and proxy server weblogic.Type 1 2 drivers.JDBC provides Connection interface that encapsulates.Using Connection interface.Set optimal row pre fetch value 2.Use Connection pool 3.Control transaction 4.Choose optimal isolation level 5.Close Connection when finished.Each of these operations effects the performance.We will walk through each.We have different approaches to establish a connection with the database, the first type of approach is.Driver. Manager. get.ConnectionString url 2.Driver. Manager. get.ConnectionString url, Properties props 3.Driver. Manager. get.ConnectionString url, String user, String password 4.Driver. connectString url, Properties propsWhen you use this approach, you can pass database specific information to the.Properties object to improve performance.For example, when you use oracle database you can pass default number of rows.Oracle has default value as 1.By increasing the value of these properties, you can reduce the number of database calls which in turn.The following code snippet illustrates this approach.Properties props new.Properties props.Row. Prefetch,3. Batch.Value,5 Connection con.Driver. Manger. get.Connectionjdbc oracle thin hoststring, props You need to figure out appropriate values for above properties for.Suppose, you want.Row. Prefetch so that you can increase performance significantly.The second type of approach is to get connection from Data.Source. You can get the connection using javax.Data. Source interface.The. advantage of getting connection from this approach is that the Data.Source works with JNDI.The implementation of Data.Source is done by vendor.The vendor. simply creates Data.Source implementation class and binds it to the JNDI tree.The. following code shows how a vendor creates implementation class and binds it to JNDI tree.Data. Source. Impl dsi new Data.Source. Impl dsi.Server. Nameoracle.Database. NameDemo Context ctx new Initial.Context ctx.DB, dsi This code registers the Data.Source. Impl object to the JNDI tree, then the.Data. Source reference from JNDI tree without knowledge of.Context ctx new Initial.Context Data.Source ds Data. Sourcectx.DB Connection con ds.Connection By using this approach we can improve performance.Nearly all. major vendor application servers like weblogic, webshpere implement the.Data. Source by taking connection from connection pool rather than a single connection.The application server creates connection pool by default.We will. discuss the advantage of connection pool to improve performance in the next.Creating a connection to the database server is expensive.It is even more. expensive if the server is located on another machine.Connection pool contains.The pool expands and.You need to. give minimum, maximum and incremental sizes as properties to the pool in order to.You get the connection from the pool rather.For example, if you give properties like min, max and incremental.There are a few choices when using connection pool.You can depend on application server if it supports this feature.Application server creates the connection pool on behalf of you when it.You need to give properties like min, max and incremental sizes to the.You can use JDBC 2.Connection. Pool.Data. Source. and Pooled.Connection if your driver implements these interfaces.Or you can create your own connection pool if you are not using any.JDBC 2. 0 compatible driver.By using any of these options, you can increase performance significantly.You need to take care of properties like min, max and incremental sizes.The. maximum number of connections to be given depends on your applications.In general, transaction represents one unit of work or bunch of code in the.To be precise, it is all or no.In JDBC, transaction is a set of one or more Statements that execute as a.
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