What is a ResultSet in Java?

A ResultSet object is a table of data representing a database result set, which is usually generated by executing a statement that queries the database. For example, the CoffeeTables. viewTable method creates a ResultSet , rs , when it executes the query through the Statement object, stmt .

Why do we use ResultSet in Java?

ResultSet interface represents the result set of a database query. A ResultSet object maintains a cursor that points to the current row in the result set. The term “result set” refers to the row and column data contained in a ResultSet object. Navigational methods − Used to move the cursor around.

What are types of ResultSet in Java?

ResultSet Types

  • 1) Forward Only (ResultSet. TYPE_FORWARD_ONLY)
  • 2) Scroll Insensitive (ResultSet.TYPE_SCROLL_INSENSITIVE.
  • 3) Scroll Sensitive (ResultSet.TYPE_SCROLL_SENSITIVE)

What is result set in JDBC?

Managing result sets with the JDBC driver

The result set is an object that represents a set of data returned from a data source, usually as the result of a query. The result set contains rows and columns to hold the requested data elements, and it is navigated with a cursor.

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How do you create a ResultSet in Java?

JDBC ResultSet and Generic Class List Using Java Reflection Annotations

  1. Create a custom annotation.
  2. Create a Model class, which contains mapping fields to the ResultSet column names with the created annotation.
  3. Call the ResultSet.
  4. Load the ResultSet for each value into the object.
  5. Check for the Primitive type.

What is use of isFirst () method?

This isFirst method is specified by the isFirst method in the java. sql. ResultSet interface. If this method is used with forward and dynamic cursors, an exception is thrown.

What is Type_scroll_insensitive in Java?

TYPE_SCROLL_INSENSITIVE means that the ResultSet can be navigated (scrolled) both forward and backwards. You can also jump to a position relative to the current position, or jump to an absolute position. The ResultSet is insensitive to changes in the underlying data source while the ResultSet is open.

What is a statement Java?

A statement specifies an action in a Java program. For example, a statement may tell the add of values of x and y and assign their sum to the variable z . It then prints a message to the standard output or writing data to a file, etc. Java statements can be broadly classified into three categories: … Expression statement.

What is JDBC in Java?

Java Database Connectivity (JDBC) is an application programming interface (API) for the programming language Java, which defines how a client may access a database. It is a Java-based data access technology used for Java database connectivity.

How do you run a query in Java?

To execute a query, call an execute method from Statement such as the following:

  1. execute : Returns true if the first object that the query returns is a ResultSet object. …
  2. executeQuery : Returns one ResultSet object.
  3. executeUpdate : Returns an integer representing the number of rows affected by the SQL statement.
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What is RS next () in Java?

The next() method of the ResultSet interface moves the pointer of the current (ResultSet) object to the next row, from the current position. Statement stmt = con. createStatement(); ResultSet rs = stmt. … And on calling the next() method for the second time the result set cursor will be moved to the 2nd row.

What happens if you call deleteRow () on a ResultSet object?

What happens if you call deleteRow() on a ResultSet object? … The row you are positioned on is deleted from the ResultSet, but not from the database.

Can we return ResultSet in Java?

Yes, just like any other objects in Java we can pass a ResultSet object as a parameter to a method and, return it from a method. The main method invokes the retrieveData() method and prints the contents of the obtained ResultSet. …

How do I convert a ResultSet to a list?

To access the database, you need to use JDBC and execute a query, giving you a ResultSet . rs.

3 Answers

  1. First you need to have a List<String> that will store all your names. …
  2. Now, you have all the records fetched and stored in ResultSet . …
  3. Now, each time you fetch one record, get the name field and add it to your list.

How do I get all the ResultSet rows?

List<ReportDescription[]> result = new ArrayList<>(); ReportDescription[] csvReportDescriptions; csvReportDescriptions = resultSet. all(). stream() . map(row -> new ReportDescription(row.

How do I find the size of a ResultSet?

println(“Total number of rows in ResultSet object = “+rowCount); Simply iterate on ResultSet object and increment rowCount to obtain size of ResultSet object in java. rowCount = rs. getRow();

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