元數(shù)據(jù): 數(shù)據(jù)庫肉康、表和字段的結(jié)構(gòu)信息
1.數(shù)據(jù)庫元數(shù)據(jù)(DatabaseMetaData)
Connection conn = new ComboPooledDataSource().getConnection();
// 獲取數(shù)據(jù)庫元數(shù)據(jù)
DatabaseMetaData metaData = conn.getMetaData();
// 獲取數(shù)據(jù)庫連接URL
String url = metaData.getURL();
// 獲取數(shù)據(jù)庫用戶名
String username = metaData.getUserName();
// 獲取數(shù)據(jù)庫驅(qū)動類名
String driverName = metaData.getDriverName();
// 獲取數(shù)據(jù)庫指定表主鍵
ResultSet rs = metaData.getPrimaryKeys(null, null, 表名);
while(rs.next()){
short seq = rs.getShort("KEY_SEQ");
String name = rs.getString("COLUMN_NAME");
}
// 獲取數(shù)據(jù)庫所有表
rs = metaData.getTables(null, null, "%", new String[]{"TABLE"});
while(rs.next()){
String tabName = rs.getString("TABLE_NAME");
System.out.println(tabName);
}
2.參數(shù)元數(shù)據(jù)(ParameterMetaData)
Connection conn = new ComboPooledDataSource().getConnection();
PreparedStatement ps = conn.prepareStatement("select * from xxx where 參數(shù)1=? and 參數(shù)2=?");
// 獲取參數(shù)元數(shù)據(jù)
ParameterMetaData metaData = ps.getParameterMetaData();
// 獲取參數(shù)個數(shù)
int count = metaData.getParameterCount();
// 獲取參數(shù)類型
String type1 = metaData.getParameterTypeName(1);
String type2 = metaData.getParameterTypeName(2);
3.結(jié)果集元數(shù)據(jù)(ResultSetMetaData)
Connection conn = new ComboPooledDataSource().getConnection();
PreparedStatement ps = conn.prepareStatement(SQL);
ResultSet rs = ps.executeQuery();
// 獲取結(jié)果集元數(shù)據(jù)
ResultSetMetaData metaData = rs.getMetaData();
// 獲取結(jié)果集列數(shù)
int cc = metaData.getColumnCount();
// 獲取結(jié)果集指定列名
String cn = metaData.getColumnName(2);
// 獲取結(jié)果集指定列類型
String ct = metaData.getColumnTypeName(3);
簡書: http://www.reibang.com/p/c2a90c72405b
CSDN博客: http://blog.csdn.net/qq_32115439/article/details/54772868
GitHub博客：http://lioil.win/2017/01/28/JDBC-MetaData.html
Coding博客：http://c.lioil.win/2017/01/28/JDBC-MetaData.html
