15.00 - Table Capacity - Teradata Database

Teradata Database Design

prodname
Teradata Database
vrm_release
15.00
category
User Guide
featnum
B035-1094-015K

Table Capacity

Table capacity is a measure of the storage space occupied by a table. Table capacity varies as a function of multi-value compression. The more values compressed, the smaller the computed value for table capacity.

“Equation 3: Uncompressed Table Capacity” defines raw table capacity in the absence of multi-value compression.

Equation 3: Uncompressed Table Capacity

where:

 

This term …

Specifies the number of …

number_of_AMPs

AMPs in the system.

base_table_header_size

bytes in the table header.

cardinality

rows in the table.

additional_nullability_presence_octets

extra presence octets required to account for the compressed values.

field_sizecol

number of bytes in a compressed column.

“Equation 4: Table Capacity for Multi-Value Compression” defines table capacity with multi‑valued compression enabled for one or more columns.

Equation 4: Table Capacity for Multi-Value Compression

where:

 

This term …

Specifies the number of …

number_of_AMPs

AMPs in the system.

base_table_header_size

bytes in the table header.

field_sizecol*

the number of table header bytes used by the compressed column + 1.

cardinality

rows in the table.

additional_nullability_presence_octets

extra presence octets required to account for the compressed multi-values.

field_sizecol

bytes in a compressed column.