Century Break - Advanced SQL Engine - Teradata Database

Database Utilities

Product
Advanced SQL Engine
Teradata Database
Release Number
17.00
Published
June 2020
Language
English (United States)
Last Update
2020-06-15
dita:mapPath
boh1556732696163.ditamap
dita:ditavalPath
lze1555437562152.ditaval
dita:id
B035-1102
lifecycle
previous
Product Category
Teradata Vantage™

Purpose

Defines how to interpret character data when converting to date. The data only has two digits representing the year, and the applicable format only has two digits representing the year. Century Break specifies which two-digit years, if any, are to be interpreted as 20th-century years and which two-digit years, if any, are to be interpreted as 21st-century years.

Field Group

General

Valid Range

0 through 100

Default

0

Changes Take Effect

When the DBS Control Record is written. For sessions logged on at the time of a change, the new setting becomes effective at the next logon, or after the next Teradata Database restart.

Rules

The following two-year digit rules apply:

IF a two-digit year yy is… THEN the year is…
less than Century Break 20yy and is considered to be in the 21st century.
greater than or equal to Century Break 19yy and is considered to be in the 20th century.

The following Century Break value rules apply:

IF Century Break is… THEN all years yy are…
0 19yy.
100 20yy.

Century Break does not affect four-digit years.

The Century Break setting has no effect on Teradata Database dates input in numeric (as opposed to character) format.

If the character data specifies a four-digit year, and the format specifies a two-digit year, Century Break does not affect the conversion. The four digits in the character data are used as the year.

Teradata recommends you convert to four-digit years and corresponding four-digit-year formats. However, Century Break provides a transitional facility while you use two-digit years.

Example: Using the Century Break DBS Control field

If Century Break = 25, strings such as '00/01/01' and '24/01/01' are interpreted as years 2000 and 2024, respectively. A string inserted as '25/01/01' is interpreted as year 1925.

The choice of 25 for Century Break indicates that the installation wants a cushion of up to 25 years to handle input dates into the 21st century and does not have historic input data prior to the year 1925.

If Century Break = 100, two-digit years are inserted as years in the 21st century (that is, 2000, 2001, and continuing on in this pattern).