Current limitations for BLOB support are as follows:

  • BLOB data columns cannot be part of an index.
  • BLOB data columns cannot be used for variables or as parameters in stored procedures.
  • Comparison operations are not supported on BLOB columns. Comparison operations between BLOB columns are not supported. Comparison operations between BLOB columns and columns of other data types are not supported.
  • Conversion, aggregate, and scalar functions are disallowed on this data type.
  • BLOB does not have National Language Support (NLS).
  • The default size for a BLOB is 32000 bytes.