Creating Tables Containing LOBs

Figure 10-3 Use Case Diagram: Four ways to Create a Table Containing a LOB

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See: "Use Case Model: Internal Persistent LOBs Operations", for all Internal Persistent LOB operations.

It is possible to incorporate LOBs into tables in four ways.

1. As columns in a table -- see Creating a Table Containing One or More LOB Columns.

2. As attributes of an object type -- see Creating a Table Containing an Object Type with a LOB Attribute.

3. Within a nested table -- see Creating a Nested Table Containing a LOB.

4. A fourth method using a Varray -- Creating a Varray Containing References to LOBs is described in Chapter 5, "Large Objects: Advanced Topics" .

In all cases SQL Data Definition Language (DDL) is used to define:

• LOB columns in a table

• LOB attributes in an object type.

Usage Notes

When creating tables that contain LOBs use the guidelines and examples described in the following sections and these chapters:

• Chapter 2, "Basic LOB Components", "Initializing Internal LOBs to NULL or Empty"

• Chapter 4, "Managing LOBs"

• Chapter 7, "Modeling and Design"