MySQL 查找指定表名的表的主键

原理

SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE 
WHERE TABLE_NAME = 表名 AND CONSTRAINT_NAME = 'PRIMARY'

方法

public static String getPk(String tableName) {
    String sql = "SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE WHERE TABLE_NAME = ? AND CONSTRAINT_NAME = 'PRIMARY'";
    PreparedStatement ps = null;
    ResultSet rs = null;
    String res = null;
    try {
        final Connection conn = JdbcUtil.getConnection();
        ps = conn.prepareStatement(sql);
        ps.setString(1, tableName);
        rs = ps.executeQuery();
        if (rs.next()) {
            res = rs.getString("COLUMN_NAME");
        }
    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        JdbcUtil.release(ps, rs);
    }
    return res;
}