This statement is ANSI SQL:2011 compliant.
As an extension to ANSI, CAST permits the use of the FORMAT phrase to enable alternative output formatting for the character representations of DateTime and Interval data.
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 TIMESTAMP. In addition, you can specify the time zone displacement using additional expressions besides an INTERVAL expression.