ResultSet

Posted 2020-06-25 wwfy

在Java中，获得ResultSet的总行数的方法有以下几种。 
第一种：利用ResultSet的getRow方法来获得ResultSet的总行数 

Java代码
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE); 
ResultSet rset = stmt.executeQuery("select * from yourTableName"); 
rset.last(); 
int rowCount = rset.getRow(); //获得ResultSet的总行数 
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE); ResultSet rset = stmt.executeQuery("select * from yourTableName"); rset.last(); int rowCount = rset.getRow(); //获得ResultSet的总行数第二种：利用循环ResultSet的元素来获得ResultSet的总行数 

Java代码
ResultSet rset = stmt.executeQuery("select * from yourTableName"); 
int rowCount = 0; 
while(rset.next()) { 
rowCount++; 
} 
ResultSet rset = stmt.executeQuery("select * from yourTableName"); int rowCount = 0; while(rset.next()) { rowCount++; }rowCount就是ResultSet的总行数。 
第三种：利用sql语句中的count函数获得ResultSet的总行数 

Java代码
ResultSet rset = stmt.executeQuery("select count(*) totalCount from yourTableName"); 
int rowCount = 0; 
if(rset.next()) { 
rowCount=rset .getInt("totalCount "); 
} 
ResultSet rset = stmt.executeQuery("select count(*) totalCount from yourTableName"); int rowCount = 0; if(rset.next()) { rowCount=rset .getInt("totalCount "); }rowCount就是ResultSet的总行数。 

• Java中获得ResultSet的总列数是非常简单事情，因为Java中ResultSet提供了ResultSetMetaData工具类,ResultSetMetaData 是ResultSet的元数据的集合说明。 
java获得ResultSet总列数的代码如下： 

Java代码
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE); 
ResultSet rset = stmt.executeQuery("select * from yourtable"); 
ResultSetMetaData rsmd = rset.getMetaData() ; 
int columnCount = rsmd.getColumnCount(); 
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE); ResultSet rset = stmt.executeQuery("select * from yourtable"); ResultSetMetaData rsmd = rset.getMetaData() ; int columnCount = rsmd.getColumnCount();columnCount 就是ResultSet的总列数。