Limitations on LOB Processing
Users should be aware of the following:
Teradata PT does not support the use of multiple APPLY when deferred LOB data types
are defined in a job schema and the LOB data is moved from one Teradata Database table
to one or more target table simultaneously.
Teradata PT does not support writing LOB data to a z/OS dataset defined by a JCL DD
statement. This means that the LOB exporting feature can only work with HFS files
on
z/OS platforms. Users cannot specify a z/OS PDS name for the location where the LOB
data files are written or for the file names.
Teradata PT does not allow a LOB column to be used in any predicate evaluation specified
in the WHERE clause or in either type of CASE expression.
If LOB data sent to Teradata Database is larger than the size of the LOB column defined
in the schema of the target table, Teradata Database truncates the data. This behavior
is consistent with the behavior of VARCHAR, VARBYTE or VARGRAPHIC column types. But
Teradata PT checks the size of a LOB data file against its schema to prevent Teradata
Database from truncating the data with no user warning.
Teradata PT checks if the LOB data file is a flat file. If it is, The SQL Inserter
operator compares the file size with the LOB column size defined in the Teradata PT
schema. If the file size is bigger, then the job is terminated with a detailed error
message.
If the LOB data source is not a file (it can be a named pipe, for instance), the SQL
Inserter operator cannot make the file size check, and thus, if the data size exceeds
the defined column size, Teradata Database truncates the data without any warning
message.