如何在 MySQL 表中分别返回两种不同类型的列(int、string)?我曾尝试使用此代码,但我无法弄清楚。请好心人,你能告诉我有什么问题吗?
请注意:::我想返回 keyid_col 和 key_col
这是我的代码:::
public void retrieve_keyword () throws SQLException{
try {
ResultSet results = statement.executeQuery
("SELECT keyword_id,key_words FROM keywordlist");
try {
while ( results.next() ) {
int numColumns =
results.getMetaData().getColumnCount();
int keyid_col = results.getInt("keyword_id");
String key_col = results.getString("key_words");
if (numColumns == 2) {
System.out.println(results.getObject(numColumns));
}
for ( int i = 1 ; i <= numColumns ; i++ ) {
System.out.println( "COLUMN " + i + " = " + results.getObject(i) );
}
}
}
catch(Exception ew){
System.out.println( ew );
}
}catch(Exception ew){
System.out.println( ew );
}
}