Question

I have to create / insert a new record in a database table (MySQL, Oracle, MSSQL) only by inserting the primary key field values. But this is not working if there is a column in the table which does not allow null values. How can I check the table columns which do not allow null values.

Answer 1

You can execute a request against your table, for example at startup time, and then check the metadata of your table:

ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM myTable");
ResultSetMetaData rsmd = rs.getMetaData();
int nullable = rsmd.isNullable(1);
if(nullable == ResultSetMetadata.columnNullable) {
    System.out.println("Nullable");
}