Oracle and SQL3 support three large object types:
BLOB : The BLOB domain type stores unstructured binary data in the database. BLOBs can store up to four gigabytes of binary data.
CLOB : The CLOB domain type stores up to four gigabytes of single-byte character set data.
NCLOB : The NCLOB domain type stores up to four gigabytes of fixed width and varyingwidth
multibyte national character set data.
These types support the following operations:
Concatenation : making up one LOB by putting two of them together.
Substring : extract a section of a LOB
Overlay : replace a substring of one LOB with another
Trim : removing particular characters (e.g. whitespace) from the beginning or end
Length : returns the length of the LOB
Position : returns the position of a substring in a LOB
Upper and Lower : turns a CLOB or NCLOB into upper or lower case