- What is the use of ResultSet?
- What happens if you call deleteRow () on a ResultSet object?
- How do I find the size of a ResultSet?
- Which packages contain the JDBC classes?
- What do you mean by ResultSet?
- What is scrollable ResultSet?
- How do you set ResultSet to first record?
- How many types of ResultSet are there in JDBC?
- Why ResultSet next is false?
- What if ResultSet is empty?
- How does ResultSet next work?
- How do I make a ResultSet scrollable?
- What is ResultSetMetaData in Java?
- What is the meaning of ResultSet dot Type_scroll_insensitive?
- How do I know if a ResultSet is closed?
- Are ResultSet updatable?
- How can you retrieve information from a ResultSet?
- Which of the following is used to call stored procedure?
- Which of the following is correct about PreparedStatement?
- Can we return ResultSet in Java?
- How do I know if a ResultSet is empty?
What is the use of ResultSet?
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..
What happens if you call deleteRow () on a ResultSet object?
The deleteRow() method of the ResultSet interface deletes the current row from the ResultSet object and from the table.
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();
Which packages contain the JDBC classes?
Explanation: The Java packages which contain JDBC classes and interfaces is Java. SQL.
What do you mean by ResultSet?
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. … A result set is effectively a table.
What is scrollable ResultSet?
A scrollable ResultSet is one which allows us to retrieve the data in forward direction as well as backward direction but no updations are allowed.
How do you set ResultSet to first record?
The ResultSet object contains a cursor/pointer which points to the current row. Initially this cursor is positioned before first row (default position). You can move the cursor of the ResultSet object to the first row from the current position, using the first() method of the ResultSet interface.
How many types of ResultSet are there in JDBC?
3There 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. It is insensitive which means any change to the database will not show change in the ResultSet while it open.
Why ResultSet next is false?
2 Answers. I believe it is the contract of try-with-resources to guarantee closing the resource specified in the try clause, after the expression finishes executing. I believe that the result set is also being closed at the end of the try block, hence calling next() returns false, because nothing is there.
What if ResultSet is empty?
If there are no rows next to its current position this method returns false, else it returns true. Therefore, soon you retrieve the ResultSet object if the first call on the next() method returns false that indicated that the obtained ResultSet object has no records.
How does ResultSet next work?
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.
How do I make a ResultSet scrollable?
Scrollable ResultSet exampleLoad the JDBC driver, using the forName(String className) API method of the Class. … Create a Connection to the database. … Create a Statement, using the createStatement() API method of the Connection. … Execute the query to the database, using the executeQuery(String sql) API method.More items…•
What is ResultSetMetaData in Java?
ResultSetMetaData is an interface in java. sql package of JDBC API which is used to get the metadata about a ResultSet object. Whenever you query the database using SELECT statement, the result will be stored in a ResultSet object. Every ResultSet object is associated with one ResultSetMetaData object.
What is the meaning of ResultSet dot Type_scroll_insensitive?
In the TYPE_SCROLL_INSENSITIVE ResultSet, the cursor moves in forward or backward directions. … This type of ResultSet is sensitive to the changes that are made in the database i.e. the modifications done in the database are reflected in the ResultSet.
How do I know if a ResultSet is closed?
The ResultSet object contains a cursor/pointer which points to the current row. Initially this cursor is positioned before first row (default position). The isClosed() method of the ResultSet interface is used to determine whether the current ResultSet object is closed.
Are ResultSet updatable?
By default, a ResultSet object is not scrollable / updatable and its cursor moves forward only. To create a to create a scrollable result set object, you can use either the ResultSet. TYPE_SCROLL_INSENSITIVE or the ResultSet.
How can you retrieve information from a ResultSet?
Retrieving Column Values from Rows The ResultSet interface declares getter methods (for example, getBoolean and getLong ) for retrieving column values from the current row. You can retrieve values using either the index number of the column or the alias or name of the column. The column index is usually more efficient.
Which of the following is used to call stored procedure?
Which of the following is used to call stored procedure? Explanation: CallableStatement is used in JDBC to call stored procedure from Java program.
Which of the following is correct about PreparedStatement?
Q 19 – Which of the following is correct about PreparedStatement? A – PreparedStatement allows mapping different requests with same prepared statement but different arguments to execute the same execution plan.
Can we return ResultSet in 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. sql. ResultSet.
How do I know if a ResultSet is empty?
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.