#include <db.h> int DB_ENV->set_blob_threshold(DB_ENV *dbenv, u_int32_t bytes, u_int32_t flags);
The DB_ENV->set_blob_threshold()
method sets
a default size for the environment which is used to determine when
a data item will be stored as a BLOB. Data items sized less than
this threshold are stored as normal data within the database. Data
items larger than this size are stored on-disk in a subdirectory
set aside for the purpose.
If this threshold value is set to 0
, then BLOB
support is turned off by default for databases created in the
environment. If this method is never called, then the default BLOB
threshold is 0
.
This method only sets the default BLOB threshold for the environment. The BLOB threshold can be set for individual databases created within the environment using DB->set_blob_threshold().
It is illegal to set a BLOB threshold if replication is enabled for the environment. That is, if the DB_INIT_REP flag is specified to DB_ENV->open().
This method configures operations performed using the specified DB_ENV handle, not all operations performed on the underlying database environment.
You may call this method at any time after the DB_ENV handle has been created.
Unless otherwise specified, the
DB_ENV->set_blob_threshold()
method returns a non-zero error value on failure and 0 on success.
The bytes parameter identifies the threshold size, in bytes, beyond which a data item is stored as a BLOB.
The DB_ENV->set_blob_threshold()
method may fail and return one of the following non-zero errors: