OraMetaData Object

Description

The OraMetaData object is returned by invoking the Describe method of the OraDatabase interface. The Describe method takes the name of a schema object, such as the emp table, and returns an OraMetaData object. The OraMetaData object provides methods for dynamically navigating and accessing all the attributes (OraMDAttribute collection) of a schema object described.

An OraMetaData object is a collection of OraMDAttribute objects that represent the description information about a particular schema object in the database. The following table is an example of attributes for a OraMetaData object of type table (ORAMD_TABLE).

Table 9-2 list the ORAMD_TABLE attributes.

Table 9-2 ORAMD_TABLE Attributes

Attribute Name	Value Type	Description
`ObjectID`	`Integer`	Object ID.
`NumCols`	`Integer`	Number of columns.
`ColumnList`	`OraMetaData`	Column list.
`IsTyped`	Boolean	Is the table typed?
`IsTemporary`	Boolean	Is the table temporary?
`Duration`	`String`	Duration - can be session, transaction, or null.
`DBA`	`Integer`	Data block address of the segment header.
`TableSpace`	`Integer`	Tablespace in which the table resides.
`IsClustered`	Boolean	Is the table clustered?
`IsPartitioned`	Boolean	Is the table partitioned?
`IsIndexOnly`	Boolean	Is the table index-only?

See Also:

"Type (OraMetaData) Property"

Remarks

The OraMetaData object can be visualized as a table with three columns:

Metadata attribute name
Metadata attribute value
Flag specifying whether the Value is another OraMetaData object

The OraMDAttribute objects contained in the OraMetaData object can be accessed by creating a subscript that uses ordinal integers or by using the name of the property. Referencing a subscript that is not in the collection (0 to Count-1) results in the return of a NULL OraMDAttribute object.

Properties

Methods

Attribute (OraMetaData) Method

Examples

See "Schema Objects Used in OraMetaData Examples" for OraMetaData schema definitions used in these examples.

The following Visual Basic example illustrates a simple use of this facility. It retrieves and displays several attributes of the emp table.

Set empMD = OraDatabase.Describe("emp") 
 
'Display the name of the Tablespace 
msgbox empMD("tablespace") 
 
'Display name, data type, and size of each column in the emp table. 
Set empColumnsMD = empMD("Columns") 
for I = 1 to empColumns.Count 
   Set ColumnMD = empColumnsMD(I) 
   MsgBox ColumnMD("Name") & ColumnMD("Data Type") & ColumnMD("Length")
Next I

Example: Describing a User-Defined Type

See "Example: Describing a User-Defined Type"

Example: Describing Unknown Schema Objects

See "Example: Describing Unknown Schema Objects"