Updatable Result Sets

The functionality of updatable resultsets in a server environment are similar to an embedded environment in Derby, with the exception of the following differences:

The Network Client requires that there be at least one column in the select list from the target table. For example, the following statement will fail in a server environment:
```
select 1, 2 from t1 for update of c11
```
The Network Client driver looks at both of the columns in the select list and cannot determine the target table for update/delete by looking at the column metadata. This requirement is not necessary in an embedded environment.
The embedded driver allows for statement name changes when there is an open resultset on the statement object. This is not supported in a server environment.

Other differences between updatable resultsets in a server or embedded environment can be found in the following table.

Table 1. Comparison of updatable resultsets features in server and embedded environments
Embedded environment	Server environment
updateString on SMALLINT, INTEGER, BIGINT, DECIMAL datatypes supported.	Not supported
updateBytes on CHAR, VARCHAR, LONG VARCHAR datatypes supported.	Not supported
updateTime on TIMESTAMP datatypes supported.	Not supported
updateObject with null values supported.	Not supported
updateClob and updateBlob supported.	Not supported