The following sections contain additional information about character datatypes.
Always use TDSVARYCHAR rather than TDSVARCHAR. DBVARYCHAR and TDSVARYCHAR objects include a length specification that precedes the data, just like DB2 variable datatypes. The length specification occupies the initial two bytes of the field (in binary format) and is referred to in print as “LL”.
In Client-Library, the CS_VARCHAR datatype
includes the “LL” length specifications and can
be mapped to TDSVARYCHAR.
TDSLONGVARCHAR objects do not have the “LL” length specification. Programs using DB2 data can send DB2 LONG VARCHAR data as TDSVARYCHAR, TDSLONGVARCHAR, or TDSTEXT.
If you use TDSVARYCHAR for LONG VARCHAR data, and if the text length is longer than 255 bytes, the data is either truncated or rejected. The truncation/rejection option is set at the TRS when it is started. The mainframe system programmer can override that option during customization.
If you convert DB2 LONG VARCHAR data to TDSLONGVARCHAR, remember that this Open ServerConnect datatype does not have the “LL” length specification. Your program should point to the data portion of the declaration only.
If your client
program is Open Client 10.0 or later, you can convert both columns
and parameters to TDSLONGVARCHAR.
Otherwise, you can use TDSLONGVARCHAR only
with columns.
If you convert to TDSTEXT, the complete data string is sent, without truncation.
