Appendix C. Porting legacy code

This section describes the migration steps for migrating from legacy code to GNADE embedded SQL. Because only a limited number of ports have been performed this section will evolve over the time.

Migrating from Oracle to GNADE

The Oracle product seems to have a lot of extension compared to ISO/92. Migrating from Oracle to GNADE using ODBC has to be done manually.

Host variables

All host variables have to be moved into the DECLARE section and the types of these variables has to be reworked as it is required by ISO/92.

Query Results

The default SQLCA with the name ORACLE does not exist. Due to the fact, that the contents of the GNADE SQLCA is different this code has to be reworked manually.

Others

The ESQL translator of Oracle supports non ISO/92 WHENEVER clauses which are supported by the GNU ESQL translator as well.

Due to the fact, that ODBC requires different parameters for the CONNECT clause this has to be reworked as well.