如何在Java中获取数据库特定的数据类型？

Question

Consider this code segment

Class.forName ("oracle.jdbc.OracleDriver");

          connection = DriverManager.getConnection
             ("jdbc:oracle:thin:@//XXX.XXX.XXX.XXX:1521/xe", "abc", "def");
 DatabaseMetaData metaData=connection.getMetaData();
        ResultSet rsc= metaData.getColumns(null, "MYSCHEMA", "MYTABLE", null);
        while (rsc.next()){

            System.out.println(rsc.getString("COLUMN_NAME").toUpperCase());
            System.out.println(rsc.getString("TYPE_NAME").toUpperCase());
            System.out.println(rsc.getInt("COLUMN_SIZE"));
            System.out.println(rsc.getInt("DECIMAL_DIGITS"));   
            System.out.println(rsc.getString("IS_NULLABLE").toUpperCase()) ;
            System.out.println(rsc.getInt("ORDINAL_POSITION"));
            System.out.println(rsc.getInt("DATA_TYPE"));
            System.out.println("********************************************");
        }

With this code segment I can get to know that if suppose MYTABLE has a column whose name is MYTABLEID of type NUMBER in Oracle then how can I get to know that what will be the corresponding datatype name of NUMBER equivalent in Mysql or PostGresql ? Basically aim is to get database specific datatype. Like in Oracle we have CLOB datatype but in postgresql we have bytea as an equivalent datatype. I wanted database specific type so that I can create DDL (Create table statement) to create table in a particular database(from oracle to mysql or postgresql etc).

Answer 1

I would create an XML file with info on each database and any specific database datatype (eg CLOB, or bytea), then I would use this info and retrieve it for any specific use you may have in your code. Hope it helps.