NAME

       odbx_lo_open - Opens a large object in the database

SYNOPSIS

       #include <opendbx/api.h>

       int odbx_lo_open (odbx_result_t* result, odbx_lo_t** lo, const char* value);

DESCRIPTION

       Some  database  management systems store large amount of data in separate regions of the database and the
       content is only referenced by identifiers in the tables. The data types used for this are  called  Binary
       Large  OBject  (BLOB)  and Character Large OBject (CLOB) and can be found in e.g. the Firebird and Oracle
       database servers. The OpenDBX library provides a large object interface to access, read and  write  their
       content  via the "odbx_lo_*()" functions. To find out if large amount of data can be accessed directly or
       if the large object interface have to be used, odbx_capabilities() provides the answer when feed with the
       ODBX_CAP_LO

       The result parameter has to be the result object created and returned by odbx_result().  It  becomes  in‐
       valid  after it was supplied to odbx_result_finish() and this function will return an error in that case.
       The second parameter, the pointer to a odbx_lo_t*, will contain the newly created large object handle  if
       odbx_lo_open() succeeds. The lo handle is necessary for all other functions of the large object interface
       so  they  are  able to perform their operations on the referenced content. The last parameter must be the
       return value of odbx_field_value() but you have to check for NULL values  before  feeding  the  value  to
       odbx_lo_open(). Otherwise, an error is returned.

RETURN VALUE

       odbx_lo_open() returns ODBX_ERR_SUCCESS, or an error code whose value is less than zero if one of the op‐
       erations  couldn't  be  completed  successfully. Possible error codes are listed in the error section and
       they can be feed to odbx_error() and odbx_error_type() to get further details.

ERRORS

       -ODBX_ERR_BACKEND
              The native database library couldn't open the large object

       -ODBX_ERR_NOMEM
              Allocating additionally required memory failed

SEE ALSO

       odbx_capabilities(), odbx_field_value(), odbx_lo_close(), odbx_lo_read(), odbx_lo_write(), odbx_result()

                                                  3 April 2024                                   odbx_lo_open(3)