For CLIv2 to provide a stable environment for existing applications, any enhancements to Teradata Database that might adversely affect applications must be specified as a DBCAREA option to allow their use. While DBCAREA specification is necessary for compatibility, this requires applications needing such enhancements to specify the new options. Since new applications should normally allow the enhancements, they should specify these DBCAREA options. Specifically, new applications should consider specifying the following options when establishing a session:
- APH-response-OK=Y (DBRIAPH) should always be specified.
- Column-info=E (DBRICINE) should always be specified.
- Connect-type=C (DBOCTYPE) should always be specified.
- Maximum-parcel=H (DBCIMP) should always be specified. For PL/I applications, the Variable-length-request=Y and Variable-length-fetch=Y options cannot then be used.
- Multi-statement-errors=Y (DBRIMSEY) should always be specified if multi-statement requests are used.
- Request-parcel-format=A (DBRIRPF) should always be specified.
- Response-mode=M (DBORMOD) instead of 'R', 'I', or 'X' should be specified ('F' provides other functionality) unless the application must support old versions of the Teradata Database, which would reject its use. The CLIv2 Query routine QEPILOB (or QEPIASL) can be used to ascertain if the Database supports this enhancement.
- Statement-status=E (DBCNISS) should be specified unless the application must support old versions of the Teradata Database, which would reject its use. The CLIv2 Query routine QEPIESS (or QEPIASL) can be used to ascertain if the Database supports this enhancement.
For applications that support multiple releases of CLIv2, a downlevel CLIv2 might not support an enlarged DBCAREA. To ensure that a DBCAREA of the size provided to the DBCHIN service was honored, the DBCAREA Level field should be verified.