Storage Structure of a Structured UDT Data Type - Teradata Vantage

Teradata® VantageCloud Lake
Deployment
VantageCloud
Edition
Lake
Product
Teradata Vantage
Published
January 2023
Language
English (United States)
Last Update
2024-04-03
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The following graphic shows the basic morphology of a structured UDT as stored in the row of a table in the database:


Basic morphology of a structured UDT

where:

UDT Element Description
Type ID TVMID type identifier for the structured UDT.

Its data type is INTEGER (4 bytes).
Presence Bits Array Octet array of presence bits for the UDT at level m of the structured UDT.

This is a variably-sized bit array, rounded to the higher modulo(8) boundary, whose size depends on the number of attributes stored for the structured UDT. Its size increases in octet (8-bit byte) increments.
Attribute n Value Attribute number n for the structured UDT.

There is a variable number of attribute value fields. The exact number depends on two factors:

  • The number of attributes the structured type has.
  • Whether an attribute is null.

The exact format of each attribute depends on the attribute type and is defined by the designer of the given structured type.