The BOOLEAN, BLOB, CLOB, and LVARCHAR data types are implemented by the database server as built-in opaque data types.
A built-in opaque data type is one for which the database server provides the type definition. Because these data types are built-in opaque types, they do not have a unique coltype value. Instead, they have one of the coltype values for opaque types: 41 (fixed-length opaque type), or 40 (varying-length opaque type). The different fixed-length opaque types are distinguished by the extended_id column in the sysxtdtypes system catalog table.
The following are the coltype values for the built-in opaque data types.
| Predefined Data Type | Value for coltype Column |
|---|---|
| BLOB
CLOB BOOLEAN LVARCHAR |
41
41 41 40 |