'NOW'

`'NOW'`

Available in: DSQL, PSQL, ESQL

Changed in: 2.0

Description: 'NOW' is not a variable but a string literal. It is, however, special in the sense that when you CAST() it to a date/time type, you will get the current date and/or time. The fractional part of the time used to be always “.0000”, giving an effective seconds precision. In Firebird 2.0 the precision is 3 decimals, i.e. milliseconds. 'NOW' is case-insensitive, and the engine ignores leading or trailing spaces when casting.

Type: CHAR(3)

Examples:

select 'Now' from rdb$database
-- returns 'Now'

select cast('Now' as date) from rdb$database
-- returns e.g. 2008-08-13

select cast('now' as time) from rdb$database
-- returns e.g. 14:20:19.6170

select cast('NOW' as timestamp) from rdb$database
-- returns e.g. 2008-08-13 14:20:19.6170

Shorthand syntax for the last three statements:

select date 'Now' from rdb$database
select time 'now' from rdb$database
select timestamp 'NOW' from rdb$database

Notes:

'NOW' always returns the actual date/time, even in PSQL modules, where CURRENT_DATE, CURRENT_TIME and CURRENT_TIMESTAMP return the same value throughout the duration of the outermost routine. This makes 'NOW' useful for measuring time intervals in triggers, procedures and executable blocks.
Except in the situation mentioned above, reading CURRENT_DATE, CURRENT_TIME and CURRENT_TIMESTAMP is generally preferable to casting 'NOW'. Be aware though that CURRENT_TIME defaults to seconds precision; to get milliseconds precision, use CURRENT_TIME(3).