HELP and SHOW Statements | ANSI Temporal Table Support | Teradata Vantage - 17.00 - HELP and SHOW Statements - Teradata Database

Teradata Vantageā„¢ - ANSI Temporal Table Support

prodname
Advanced SQL Engine
Teradata Database
vrm_release
17.00
created_date
June 2020
category
Programming Reference
featnum
B035-1186-170K
HELP and SHOW statements display information that is relevant to ANSI temporal tables:
  • HELP COLUMN output includes a Temporal Column field that displays V, S, R, or N, to indicate a valid-time, system-time, temporal relationship constraint, or nontemporal column, respectively. (Note that temporal relationship constraints are allowed on ANSI temporal tables, but are not themselves ANSI-compliant.)
  • HELP COLUMN also includes fields named Without Overlaps Unique for ANSI temporal tables that include a valid-time column. The values of this field can be Y or N.
  • HELP CONSTRAINT has a Type field that shows information about named constraints, including temporal constraints. Note that HELP CONSTRAINT shows information only about named constraints. Use SHOW TABLE to see information about unnamed constraints defined on tables.
  • HELP SESSION includes a Temporal Qualifier field that shows ANSIQUALIFIER if the session temporal qualifier is set to ANSIQUALIFIER, a requirement for working with ANSI temporal tables, that is normally set automatically.
  • HELP TRIGGER includes ValidTime Type and TransactionTime Type fields that display A to indicate trigger has been created on an ANSI temporal table.
  • SHOW TABLE displays these additional items for ANSI temporal tables:
    • VALIDTIME and SYSTEM_TIME derived period columns and their component beginning and ending bound Date/Timestamp columns.
    • SYSTEM VERSIONING for system-versioned system-time tables.
    • temporal PRIMARY KEY and UNIQUE constraint definitions having WITHOUT OVERLAPS.
    • Temporal referential integrity constraints with referencing and referenced period specifications.