15.00 - Table Sizing Equations - Teradata Database

Teradata Database Design

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

Table Sizing Equations

The following parameter definitions are used with this equation set:

 

              Parameter

                                                     Definition

Block Overhead

Block Header + Block Trailer = 72 bytes + 2 bytes = 74 bytes

Minimum Table Header Size

512 bytes

Typical Block Size

Number of bytes per block (see “Calculating a Typical Block Size” on page 859).

NumAmps

Number of AMPs in the configuration.

RowCount

Estimated cardinality for the table.

Average RowSize

Physical row size for the table (see “Row Size Calculation” on page 846).

Remember that all row lengths must be an even number of bytes (see “Byte Alignment” on page 770), so be sure to take this into account.

Example : Table, Hash, or Join Index on a Packed64 Format System

You have collected the following information.

 

                                     Parameter

                                       Value

Block size

5,120 bytes

Note: Typical block size used.

Number of AMPs

20

Row count

1,000,000

Row size

100 bytes

Rows per block are rounded down.

Number of blocks are rounded up.

Calculate the size of this object when it is defined with fallback.