JAVA/JSP Learning Series 5 (JDBC-ODBC flip example) _ MySQL

1. before running, we recommend that you use MSSQLServer7 database DNS. The name is: Test_DB. there is a table in the database: guestbook field: name (varchar), email (varchar), body (text) the sa password is blank for database users and can be modified by themselves. II. code % @ pagecontentTypetexthtml; charsetgb2312 % variable declaration JDBCODBC

I. preparations before running

We recommend that you create a DNS for the MS SQLServer7 database named Test_DB.

There is a table in the database: guestbook field: name (varchar), email (varchar), body (text)

The sa password is blank for database users and can be modified by themselves.

II. code

<% @ Page contentType = "text/html; charset = gb2312" %>

<%

// Variable declaration

Java. SQL. Connection sqlCon; // database Connection object

Java. SQL. Statement sqlStmt; // SQL Statement object

Java. SQL. ResultSet sqlRst; // result set object

Java. lang. String strCon; // database connection String

Java. lang. String strSQL; // SQL statement


Int intPageSize; // number of records displayed on one page

Int intRowCount; // The total number of records.

Int intPageCount; // The total number of pages.

Int intPage; // The page number to be displayed.

Java. lang. String strPage;

Int I, j, k; // set the number of records displayed on one page

IntPageSize = 5; // get the page number to be displayed

StrPage = request. getParameter ("page ");

If (strPage = null ){

// Indicates that the QueryString parameter does not contain the page parameter. The first page of data is displayed.

IntPage = 1;

} Else {

// Converts a string to an integer.

IntPage = java. lang. Integer. parseInt (strPage );

If (intPage <1) intPage = 1 ;}

// Load the JDBC-ODBC driver

Class. forName ("sun. jdbc. odbc. JdbcOdbcDriver ");

// Set the database connection string

StrCon = "jdbc: odbc: Test_DB ";

// Connect to the database

SqlCon = java. SQL. DriverManager. getConnection (strCon, "sa ","");

// Create an SQL statement object

SqlStmt = sqlCon. createStatement ();

// Obtain the total number of records

StrSQL = "select count (*) from guestbook ";

SqlRst = sqlStmt.exe cuteQuery (strSQL );

// Execute the SQL statement and obtain the result set

SqlRst. next (); // when the record set is opened, the pointer is located before the first record.

IntRowCount = sqlRst. getInt (1 );

SqlRst. close (); // close the result set.



// Calculate the total number of pages

IntPageCount = (intRowCount + intPageSize-1)/intPageSize;

// Adjust the page number to be displayed if (intPage> intPageCount) intPage = intPageCount;

// Set the SQL statement for getting data

StrSQL = "select name, email, body from guestbook ";

// Execute the SQL statement and obtain the result set

SqlRst = sqlStmt.exe cuteQuery (strSQL );