What if resultset is empty

An SQL result set is a set of rows from a database, as well as metadata about the query such as the column names, and the types and sizes of each column. Depending on the database system, the number of rows in the result set may or may not be known. How do you handle null values in Java? But enough bragging, here's my list of practices when dealing with null values.

Don't Overcomplicate Things. Use Objects Methods as Stream Predicates. Never Pass Null as an Argument. Leverage Optional. Return Empty Collections Instead of Null. Optional Ain't for Fields. Use Exceptions Over Nulls. The cursor can only move forward in the result set. The cursor can scroll forward and backward, and the result set is not sensitive to changes made by others to the database that occur after the result set was created.

What is the use of wasNull in ResultSet interface? The wasNull method of the ResultSet interface determines whether the last column read had a Null value. What is RS next in Java? The next moves the cursor froward one row from its current position in the resultset. Now w. Can we use two ResultSet in Java? So what is the purpose of "if rs! It seems that these java methods on the resultSet return false if the resultSet has no rows. David Peterson. If you use a do.. Consider Paul's rocket mass heater.

Boost this thread! Action problem. Action form: data getting lost between form submit and setters on ActionForm. Null vs empty string.

You are re-using the Statement that was used to produce rs on the last line of your loop. A ResultSet object is automatically closed when the Statement object that generated it is closed, re-executed, or used to retrieve the next result from a sequence of multiple results.

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. Moves the cursor down one row from its current position. This method return true if there's another row or false otherwise. Example of PreparedStatement to insert records until user press n import java. To return result sets from a Java method Ensure that the Java method is declared as public and static in a public class.

For each result set you expect the method to return , ensure that the method has a parameter of type java. ResultSet []. You can try using two different Statement instances for each query. See the JavaDoc for java. To iterate the ResultSet you use its next method. The next method returns true if the ResultSet has a next record, and moves the ResultSet to point to the next record.

If there were no more records, next returns false, and you can no longer. ResultSet returned is never null even if there are no records matching the query. To execute a query, call an execute method from Statement such as the following: execute : Returns true if the first object that the query returns is a ResultSet object.

There are 3 basic types of ResultSet. As name suggest, this type can only move forward and are non-scrollable. This type is scrollable which means the cursor can move in any direction.