CAST TIMESTAMP-to-TIME Conversion | VantageCloud Lake - TIMESTAMP-to-TIME Conversion with CAST - Teradata VantageCloud Lake

ANSI Compliance

This statement is ANSI SQL:2011 compliant.

As an extension to ANSI, CAST permits the use of TIME data attribute phrases.

The AT clause is ANSI SQL:2011 compliant.

As an extension to ANSI, the AT clause is supported when using CAST to convert from TIMESTAMP to TIME. In addition, you can specify the time zone displacement using additional expressions besides an INTERVAL expression.

Syntax

CAST (
  timestamp_expression AS TIME
  
  [ ( fractional_seconds_precision ) ]
  
  [ WITH TIME ZONE ]
  
  [ AT { LOCAL | SOURCE [ TIME ZONE ] |
         [ TIME ZONE ] { expression | time_zone_string }
       }
  ]
  
  [ data_attribute [...] ]
)

Syntax Elements

timestamp_expression

The timestamp expression to be converted.

fractional_seconds_precision

A single digit representing the number of significant digits in the fractional portion of the SECOND field. The valid range is 0 through 6. The default is 6.

AT LOCAL

Use the time zone displacement based on the current session time zone.

AT SOURCE [TIME ZONE]

Use the time zone associated with timestamp_expression when:

• AT SOURCE TIME ZONE is specified.
• AT SOURCE is specified without TIME ZONE and there is no column named source in the scope.

Otherwise, if AT SOURCE is specified without TIME ZONE and a column named source exists, then SOURCE references this column, and the value of the column is used as the time zone displacement for the CAST. If needed, the column value is implicitly converted to type INTERVAL HOUR(2) TO MINUTE.

AT [TIME ZONE] expression

Use the time zone displacement defined by expression.

The data type of expression must be INTERVAL HOUR(2) TO MINUTE or it must be a data type that can be implicitly converted to INTERVAL HOUR(2) TO MINUTE.

AT [TIME ZONE] time_zone_string

time_zone_string determines the time zone displacement.

data_attribute

One of the following data attributes:

• FORMAT
• NAMED
• TITLE