Can you return a ResultSet in Java?

Can you return a 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. ...

What is the return type of ResultSet in Java?

A ResultSet object maintains a cursor pointing to its current row of data. ... The next method moves the cursor to the next row, and because it returns false when there are no more rows in the ResultSet object, it can be used in a while loop to iterate through the result set.

Can we reuse ResultSet?

As soon as you execute the 2nd query, the previous ResultSet is automatically closed. And as far as Garbage Collection is concerned, you don't have to worry about that. You can just have a stmt.

Is ResultSet empty Java?

The JDBC ResultSet doesn't provide any isEmpty(), length() or size() method to check if its empty or not. Hence, when a Java programmer needs to determine if ResultSet is empty or not, it just calls the next() method and if next() return false it means ResultSet is empty.

What is RS next () in Java?

The ResultSet object has a cursor/pointer which points to the current row. Initially this cursor is positioned before first row. The next() method of the ResultSet interface moves the pointer of the current (ResultSet) object to the next row, from the current position.

How does ResultSet work 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 .

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 ResultSet 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.

Can JDBC statement be reused?

Statement is an interface, actual class can be anything JDBC driver returns. In general you can not reuse one statement class for another type. For example, CallableStatement and PreparedStatement (for oracle JDBC) are incompatible. As for ResultSet, closing it releases database cursor, at least in some scenarios.

Can I reuse a PreparedStatement?

Once a PreparedStatement is prepared, it can be reused after execution. You reuse a PreparedStatement by setting new values for the parameters and then execute it again.

What is the purpose of resultset in Java?

It is used to store the data which are returned from the database table after the execution of the SQL statements in the Java Program. The object of ResultSet maintains cursor point at the result data.

Can a Java query return two result sets at once?

The above query returns two result sets at once, and I cannot fire both queries separately. How can I handle both the result set at once in a Java class? getMoreResults () and execute () return false to indicate that the result of the statement is just a number and not a ResultSet.

How to process multiple result sets in Java?

Correct code to process multiple ResultSet s returned by a JDBC statement: getMoreResults () and execute () return false to indicate that the result of the statement is just a number and not a ResultSet. You need to check stmt.getUpdateCount () == -1 to know if there are more results.

How does the JDBC resultset retrieve the data?

It will return FALSE if there are no more records. It retrieves data by calling the executeQuery () method using any of the statement objects. It may be Statement or PreparedStatement or CallableStatement object. PreparedStatement, and CallableStatement interfaces are the sub-interfaces of the Statement interface.