A ResultSet is a Java object that contains the results of executing an SQL query. In other words, it contains the rows that satisfy the conditions of the query. The data stored in a ResultSet object is retrieved through a set of get methods that allows access to the various columns of the current row.Also to know is, what are the types of ResultSet?
There are 3 basic types of ResultSet.
- Forward-only. As name suggest, this type can only move forward and are non-scrollable.
- Scroll-insensitive. This type is scrollable which means the cursor can move in any direction.
- Scroll-sensitive.
- Forward-only.
- Scroll-insensitive.
- Scroll-sensitive.
Furthermore, what is ResultSet in JDBC with example? 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 .
Additionally, what is ResultSet statement?
The SQL statements that read data from a database query, return the data in a result set. 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.
What is the meaning of ResultSet Type_scroll_insensitive?
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.
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[].What is JDBC connection?
Java Database Connectivity (JDBC) is an application programming interface (API) for the programming language Java, which defines how a client may access a database. A JDBC-to-ODBC bridge enables connections to any ODBC-accessible data source in the Java virtual machine (JVM) host environment.What is callable statement?
CallableStatement is used to execute SQL stored procedures. The type of all OUT parameters must be registered prior to executing the stored procedure; their values are retrieved after execution via the get methods provided here. A Callable statement may return a ResultSet or multiple ResultSets.Can ResultSet be null in Java?
No, ResultSet returned by executeQuery(java. lang. String) method can never be null. Moreover, the standard way to check whether a ResultSet is empty or not is to try setting its cursor to first row by using its first() and if it returns false it indicates that ResultSet is empty.What is prepared statement in SQL?
A prepared statement is a feature used to execute the same (or similar) SQL statements repeatedly with high efficiency. Prepared statements basically work like this: Execute: At a later time, the application binds the values to the parameters, and the database executes the statement.What is PreparedStatement in JDBC?
PreparedStatement is a class in java.sql package and allows Java programmer to execute SQL queries by using JDBC package. You can get PreparedStatement object by calling connection.prepareStatement() method.SQL queries passed to this method goes to Database for pre-compilation if JDBC driver supports it.Are resultsets updateable?
Updatable Resultset. Whenever we create a ResultSet object which never allows us to update the database through ResultSet object and it allows retrieving the data only in forward direction. Such type of ResultSet is known as non-updatable and non-scrollable ResultSet.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. In order to make the non-scrollable ResultSet as scrollable ResultSet we must use the following createStatement() method which is present in Connection interface.How do I know if a ResultSet is null?
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 the difference between ResultSet and ResultSetMetaData?
ResultSetMetaData is a class that is used to find information about the ResultSet returned from a executeQuery call. It contains information about the number of columns, the types of data they contain, the names of the columns, and so on.What happens if ResultSet is not closed?
What will happen when ResultSet is not closed? In a pooled database connection, it is returned to the pool and could close only after expiring its life time. If it happens on a single database by multiple applications, the data updation is not perfect and may violate ACID properties rule for data presuming.How many types of statements are available in JDBC?
three types
How do you size 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.Do we need to close ResultSet in Java?
No you are not required to close anything BUT the connection. Per JDBC specs closing any higher object will automatically close lower objects. Closing Connection will close any Statement s that connection has created. Closing any Statement will close all ResultSet s that were created by that Statement .What is the difference between statement and PreparedStatement interface?
While the Statement interface is a general purpose carrier used to execute static SQL statements, PreparedStatement is a parameterized statement used to execute dynamic SQL statements.What is RS next () in Java?
The next() moves the cursor froward one row from its current position in the resultset . so its evident that if(rs. next()) means that if the next row is not null (means if it exist), Go Ahead. Now w.r.t your problem, ResultSet rs = stmt. executeQuery(sql); //This is wrong ^What is a statement in Java?
Java statements are instructions that tell the programming language what to do, like declaration and string statements. Basic statements define variables and initiate Java methods or start the execution of blocks of other statements. Assignment statements assign values to variables. 
