15.00 - Data Type Size Differences For Packed64 and Aligned Row Format Architectures - Teradata Database

Teradata Database Design

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

Data Type Size Differences For Packed64 and Aligned Row Format Architectures

Several data types have different sizes depending on whether the rows of a system are formatted using a packed64 or an aligned row format. The row size increases for aligned row formats are not all due to increased data type sizes. Byte alignment issues also play a significant role in this increase. Furthermore, neither study examined the effects of the increased data block header size introduced by WAL on storage (see“Byte Alignment” on page 770 for more information).

The following table lists the predefined data types that have different disk storage sizes for packed64 and aligned row formats. If a data type is not listed in the table, then its allocated size is identical for packed64 format and aligned row format systems.

 

                             Data Type

 

       Packed64

     Format Size          (bytes)

     Aligned Row      Format Size          (bytes)

       Allocated         Aligned      Format Size          (bytes)

TIME

              6

             4

               8

TIMESTAMP

            10

             4

             12

INTERVAL DAY TO SECOND

            10

             4

             12

INTERVAL MINUTE TO SECOND

              6

             4

               8

INTERVAL SECOND

              6

             4

               8