The database server uses the LVARCHAR data type to transfer the
external text representation of an opaque data type between the database
server and an application. Although the actual internal, binary representation
for the opaque data type might contain nontext types, such as integers
or double precision floating-point values, the data in its external
text format is an LVARCHAR. The input and output support functions
serve as cast functions between the LVARCHAR and opaque data types.
Tip: Columns of type LVARCHAR are limited to 32,739 bytes. However,
you can use LVARCHAR columns to transport opaque data with a maximum
length of the data string of 2 gigabytes. The available memory on
your system might restrict this limit to a lower value.
The DataBlade® API provides
the mi_lvarchar data type to hold the external representation
of opaque-type data. For more information, see the HCL OneDB™
DataBlade API Programmer's
Guide.
applications
use lvarchar to transfer the external text representation of
an opaque type. The database server implicitly invokes the input and
output support functions when it receives an SQL statement that contains
an lvarchar host variable.
ESQL/C applications use varbinary to transfer the external
binary representation of an opaque type.