Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
Java Articles
Page 386 of 450
Java Connection getSystemFunctions() method with example
This method retrieves the list of System functions supported by the current database. The names returned by this method are the Open CLI System function names.This method returns a String value holding the list of functions separated by commas (", ").To get the list of the System functions supported by the underlying database −Make sure your database is up and running.Register the driver using the registerDriver() method of the DriverManager class. Pass an object of the driver class corresponding to the underlying database.Get the connection object using the getConnection() method of the DriverManager class. Pass the URL the database and, user ...
Read MoreJava DatabaseMetaData getSearchStringEscape() method with example
The getSearchStringEscape() method of the DatabaseMetaData interface is used to get the that is used to escape the wildcard characters ('_' or, '%') by the underlying database.This method returns a string parameter representing the value that is used to escape wildcard charactersTo get the DatabaseMetaData object −Make sure your database is up and running.Register the driver using the registerDriver() method of the DriverManager class. Pass an object of the driver class corresponding to the underlying database.Get the connection object using the getConnection() method of the DriverManager class. Pass the URL the database and, user name, password of a user in the database, ...
Read MoreJava ResultSet isBeforeFirst() method with example
When we execute certain SQL queries (SELECT query in general) they return tabular data.The java.sql.ResultSet interface represents such tabular data returned by the SQL statements.i.e. the ResultSet object holds the tabular data returned by the methods that execute the statements which quires the database (executeQuery() method of the Statement interface in general).The ResultSet object has a cursor/pointer which points to the current row. Initially this cursor is positioned before first row.The isBeforeFirst() method of the ResultSet interface is used to determine whether the cursor is at the default position of the ResultSet.rs.isBeforeFirst();This method returns an boolean this value is true, if the cursor is ...
Read MoreJava ResultSet isClosed() method with example
When we execute certain SQL queries (SELECT query in general) they return tabular data.The java.sql.ResultSet interface represents such tabular data returned by the SQL statements.i.e. the ResultSet object holds the tabular data returned by the methods that execute the statements which quires the database (executeQuery() method of the Statement interface in general).The ResultSet object has a cursor/pointer which points to the current row. Initially this cursor is positioned before first row.The isClosed() method of the ResultSet interface is used to determine whether the current ResultSet object is closed.rs.isclosed()CLOSE_CURSORS_AT_COMMITIf the holdability of the ResultSet object is set to this value. Whenever you commit/save ...
Read MoreHow to retrieve the contents of a ResultSet from last to first in JDBC?
ResultSet objectCertain SQL queries (especially SELECT) returns tabular data, In JDBC the object of the java.sql.ResultSet interface holds the tabular data returned by the methods that execute the statements which quires the database (executeQuery() method of the Statement interface in general).ResultSet Cursor/pointerThe ResultSet object has a cursor/pointer which points to the current row. Initially this cursor is positioned before first row.There are two types of result sets namely, forward only and, bidirectional. By default the ResultSet we get by the executeQuery() method is of the type forward only. Using this you can traverse/move the cursor only forward direction.Bidirectional ResultSetA bi-directional ResultSet ...
Read MoreHow to move the ResultSet cursor to the next row in JDBC?
Whenever we execute SQL statements using the executeQuery() method, it returns a ResultSet object which holds the tabular data returned by the SELECT queries(in general).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 next row from the current position, using the next() method of the ResultSet interface.rs.next()This method returns a boolean value specifying whether the ResultSet object contains more rows.If there are no rows next to its current position this method returns false, else it returns true.Let us create ...
Read MoreHow to move the ResultSet cursor to the previous row in JDBC?
Whenever we execute SQL statements using the executeQuery() method, it returns a ResultSet object which holds the tabular data returned by the SELECT queries(in general).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 previous row from the current position, using the previous() method of the ResultSet interface.rs.previous()This method returns a boolean value specifying whether the ResultSet object contains more rows. If there are no rows before its current position this method returns false, else it returns true.Let us ...
Read MoreHow to get all table names from a database using JDBC?
You can get the list of tables in the current database in MySQL using the SHOW TABLES query.Show tables;Following JDBC program retrieves the list of tables in the database by executing the show tables query.Exampleimport java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; public class ListingTables { public static void main(String args[]) throws Exception { //Registering the Driver DriverManager.registerDriver(new com.mysql.jdbc.Driver()); //Getting the connection String mysqlUrl = "jdbc:mysql://localhost/mydatabase"; Connection con = DriverManager.getConnection(mysqlUrl, "root", "password"); System.out.println("Connection established......"); //Creating a Statement object ...
Read MoreHow to get column count in a ResultSet in JDBC?
You can get the column count in a table using the getColumnCount() method of the ResultSetMetaData interface. On invoking, this method returns an integer representing the number of columns in the table in the current ResultSet object.//Retrieving the ResultSetMetaData object ResultSetMetaData rsmd = rs.getMetaData(); //getting the column type int column_count = rsmd.getColumnCount();Let us create a table with name employee_data in MySQL database using CREATE statement as shown below −CREATE TABLE employee_data( id INT, Name VARCHAR(255), DOB date, Location VARCHAR(40) );Following JDBC program establishes connection with the database, retrieves the ResultSetMetaData object of the employee_data table, and prints the number of columns in it.Exampleimport ...
Read MoreHow to Maintain an open ResultSet after commit in JDBC?
ResultSet holdability determines whether the ResultSet objects (cursors) should be closed or held open when a transaction (that contains the said cursor/ ResultSet object) is committed using the commit() method of the Connection interface.ResultSet interface provides two values to specify the holdability namely CLOSE_CURSORS_AT_COMMIT and HOLD_CURSORS_OVER_COMMITIf the holdability of the ResultSet object is set to this value. Whenever you commit/save a transaction using the commit() method of the Connection interface, the ResultSet objects created in the current transaction (that are already opened) will be held open.Therefore, if you need to hold the ResultSet cursor open after the commit automatically, set ...
Read More