DBMS_AQ, 3 of 24

Type Name

The type_name data structure defines queue types.

Syntax

type_name := VARCHAR2;
type_name := <object_type> | "RAW";

Attributes

Table 4-3 Type Name Attributes

Attribute Description

Attribute	Description
<object_types>	Maximum number of attributes in the object type is limited to 900. See Also: Oracle9i Database Concepts
"RAW"	To store payload of type `RAW`, AQ creates a queue table with a `LOB` column as the payload repository. The theoretical maximum size of the message payload is the maximum amount of data that can be stored in a `LOB` column. However, the maximum size of the payload is determined by which programmatic environment you use to access AQ. For PL/SQL, Java and precompilers the limit is 32K; for the OCI the limit is 4G. Because the PL/SQL enqueue and dequeue interfaces accept `RAW` buffers as the payload parameters you will be limited to 32K bytes. In OCI, the maximum size of your `RAW` data will be limited to the maximum amount of contiguous memory (as an `OCIRaw` is simply an array of bytes) that the OCI Object Cache can allocate. Typically, this will be at least 32K bytes and much larger in many cases. Because `LOB` columns are used for storing `RAW` payload, the AQ administrator can choose the `LOB` tablespace and configure the `LOB` storage by constructing a `LOB` storage string in the `storage_clause` parameter during queue table creation time.

<object_types>

Maximum number of attributes in the object type is limited to 900.

See Also: Oracle9i Database Concepts

"RAW"

To store payload of type RAW, AQ creates a queue table with a LOB column as the payload repository. The theoretical maximum size of the message payload is the maximum amount of data that can be stored in a LOB column. However, the maximum size of the payload is determined by which programmatic environment you use to access AQ. For PL/SQL, Java and precompilers the limit is 32K; for the OCI the limit is 4G. Because the PL/SQL enqueue and dequeue interfaces accept RAW buffers as the payload parameters you will be limited to 32K bytes. In OCI, the maximum size of your RAW data will be limited to the maximum amount of contiguous memory (as an OCIRaw is simply an array of bytes) that the OCI Object Cache can allocate. Typically, this will be at least 32K bytes and much larger in many cases.

Because LOB columns are used for storing RAW payload, the AQ administrator can choose the LOB tablespace and configure the LOB storage by constructing a LOB storage string in the storage_clause parameter during queue table creation time.