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How to group queries using transaction in a JSP?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jul-2019 328 Views

The tag is used to group the and tags into transactions. You can put as many and tags as statements inside the tag to create a single transaction.It ensures that the database modifications performed by the nested actions are either committed or rolled back if an exception is thrown by any nested action.AttributeThe tag has the following attributes −AttributeDescriptionRequiredDefaultdataSourceDatabase connection to use (overrides the default)NoDefault databaseisolationTransaction isolation (READ_COMMITTED, READ_UNCOMMITTED, REPEATABLE_READ, or SERIALIZABLE)NoDatabase’s defaultExampleTo start with the basic concept, let us create a Students table in the TEST database and create a few records ...

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How to process SQL statements with JDBC explain with an example?

Daniol Thomas
Daniol Thomas
Updated on 30-Jul-2019 6K+ Views

To process an SQL statement, you need to follow the steps given below:Establish the connection.Create a statement.Execute the statement/query.Process the result.Close the connection.Establishing a ConnectionTo process SQL statements first of all you need to establish connection with the desired DBMS or, file System or, other data sources.To do so, Register the JDBC driver class, corresponding to the DataSource you need to the DriverManager using the registerDriver() method.Driver myDriver = new com.mysql.jdbc.Driver(); DriverManager.registerDriver(myDriver);This method accepts an object of the Driver class; it registers the specified Driver with the DriverManager.You can also register the driver using the forName() method. This method loads ...

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What is the difference between the TYPE_SCROLL_INSENSITIVE and TYPE_SCROLL_SENSITIVE ResultSets in JDBC?

Krantik Chavan
Krantik Chavan
Updated on 30-Jul-2019 2K+ Views

In the TYPE_SCROLL_INSENSITIVE ResultSet, the cursor moves in forward or backward directions. This type of ResultSet is insensitive to the changes that are made in the database i.e. the modifications done in the database are not reflected in the ResultSet.Which means if we have established a connection with a database using a JDBC program and retrieved a ResultSet holding all the records in a table named SampleTable. Meanwhile, if we have added some more records to the table (after retrieving getting the ResultSet), these recent changes will not be reflected in the ResultSet object we previously obtained.In the TYPE_SCROLL_SENSITIVE ResultSet, ...

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Can we test XPath expression in JSP?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jul-2019 292 Views

The tag evaluates a test XPath expression and if it is true, it processes its body. If the test condition is false, the body is ignored.AttributeThe tag has the following attributes −AttributeDescriptionRequiredDefaultselectThe XPath expression to be evaluatedYesNonevarName of the variable to store the condition's resultNoNonescopeScope of the variable specified in the var attributeNoPageExampleFollowing is an example that show the use of the tag −           JSTL x:if Tags               Books Info:                           ...

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What is ResultSet Concurrency in JDBC?

Krantik Chavan
Krantik Chavan
Updated on 30-Jul-2019 2K+ Views

The concurrency of the ResultSet object determines whether its contents can be updated or not.The Connection interface provides 3 variants of the createStatement() method where one of the method's signature is as follows:Statement createStatement(int resultSetType, int resultSetConcurrency)This method accepts two integer type variables where one represents the type of the ResultSet and the other represents the Concurrency of the ResultSet.The ResultSet interface provides two values to specify the concurrency of the ResultSet.CONCUR_READ_ONLY: If you set this as a value of the concurrency while creating the ResultSet object you cannot update the contents of the ResultSet you can only read/retrieve them.CONCUR_UPDATABLE: ...

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Can we have a switch statement in JSP for XPath expression?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jul-2019 504 Views

The tag works like a Java switch statement. With this, you can choose between a number of alternatives. Where the switch statement has the case statements, the tag has the tags. In a similar way, a switch statement has the default clause to specify a default action and the tag has the tag as the default clause.AttributeThe tag does not have any attribute.The tag has one attributes which is listed below.The tag does not have any attribute.The tag has the following attributes −AttributeDescriptionRequiredDefaultselectCondition to evaluateYesNoneExample         ...

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What is CONCUR_READ_ONLY ResultSet in JDBC? Explain?

Krantik Chavan
Krantik Chavan
Updated on 30-Jul-2019 3K+ Views

In general, you will pass this as a value to the createStatement() method as a value of ResultSet Concurrency type.Statement createStatement(int resultSetType, int resultSetConcurrency)This type of result set is not updatable. i.e. once you get a ResultSet object you cannot update its contents.ExampleSuppose, we have a table named Employee in the database with the following contents:+----+---------+--------+----------------+ | Id | Name    | Salary | Location       | +----+---------+--------+----------------+ | 1  | Amit    | 3000   | Hyderabad      | | 2  | Kalyan  | 4000   | Vishakhapatnam | | 3  | Renuka  | 6000   ...

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How to insert rows into a ResultSet in JDBC?

Nancy Den
Nancy Den
Updated on 30-Jul-2019 1K+ Views

You can retrieve the contents of a table as a ResultSet and, insert a new row to it directly. To do so, first of all, you need to make sure your ResultSet is updatable.The moveToInsertRow() method of the ResultSet interface navigates the cursor to the position where you need to insert the next record. Therefore, move the cursor to the appropriate position to insert a row using this method.The updateXXX() methods of the ResultSet interface allows you to insert/update values into the ResultSet object.Add values to the new row using these methods for example if you need to insert an ...

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Fetch the value from Decade Tuple in Java

Arjun Thakur
Arjun Thakur
Updated on 30-Jul-2019 138 Views

To fetch the value from Decade Tuple in Java, use the getAtX() method. Here, X represents the index value like getAt1() at index 1. This will return the element at index 1 in the Tuple.Let us first see what we need to work with JavaTuples. To work with Decade class in JavaTuples, you need to import the following packageimport org.javatuples.Decade;Note Download JavaTuples Jar library to run JavaTuples program. If you are using Eclipse IDE, then Right Click Project -> Properties -> Java Build Path -> Add External Jars and upload the downloaded JavaTuples jar file. Refer the below guide for ...

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Set Decade value in JavaTuples

Chandu yadav
Chandu yadav
Updated on 30-Jul-2019 159 Views

To set a new value in the Decade Tuple, you need to use the setAtX() method. Here, X is the index wherein you want to set the value. For example, setAt2() sets the value at index 2. The value to be included is to be set as the value in the parameter, likesetAt2(“Amit”);Let us first see what we need to work with JavaTuples. To work with Decade class in JavaTuples, you need to import the following packageimport org.javatuples.Decade;Note Download JavaTuples Jar library to run JavaTuples program. If you are using Eclipse IDE, then Right Click Project -> Properties -> Java ...

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