The TIMESTAMP and TIMESTAMPTZ data types stores a date and time pair in UTC.
Variants
TIMESTAMP has two variants:
TIMESTAMPpresents allTIMESTAMPvalues in UTC.TIMESTAMPTZconvertsTIMESTAMPvalues from UTC to the client's session time zone (unless another time zone is specified for the value). However, it is conceptually important to note thatTIMESTAMPTZdoes not store any time zone data.Note:The default session time zone is UTC, which means that by default
TIMESTAMPTZvalues display in UTC.
The difference between these two variants is that TIMESTAMPTZ uses the client's session time zone, while the other simply does not. This behavior extends to functions like now() and extract() on TIMESTAMPTZ values.
Best practices
We recommend always using the TIMESTAMPTZ variant because the TIMESTAMP variant can sometimes lead to unexpected behaviors when it ignores a session offset. However, we also recommend you avoid setting a session time for your database.
Aliases
In CockroachDB, the following are aliases:
TIMESTAMP,TIMESTAMP WITHOUT TIME ZONETIMESTAMPTZ,TIMESTAMP WITH TIME ZONE
Syntax
A constant value of type TIMESTAMP/TIMESTAMPTZ can be expressed using an
interpreted literal, or a
string literal
annotated with
type TIMESTAMP/TIMESTAMPTZ or
coerced to type
TIMESTAMP/TIMESTAMPTZ.
TIMESTAMP constants can be expressed using the
following string literal formats:
| Format | Example |
|---|---|
| Date only | TIMESTAMP '2016-01-25' |
| Date and Time | TIMESTAMP '2016-01-25 10:10:10.555555' |
| ISO 8601 | TIMESTAMP '2016-01-25T10:10:10.555555' |
To express a TIMESTAMPTZ value (with time zone offset from UTC), use
the following format: TIMESTAMPTZ '2016-01-25 10:10:10.555555-05:00'
When it is unambiguous, a simple unannotated string literal can also
be automatically interpreted as type TIMESTAMP or TIMESTAMPTZ.
Note that the fractional portion is optional and is rounded to microseconds (6 digits after decimal) for compatibility with the PostgreSQL wire protocol.
Size
A TIMESTAMP/TIMESTAMPTZ column supports values up to 12 bytes in width, but the total storage size is likely to be larger due to CockroachDB metadata.
Examples
> CREATE TABLE timestamps (a INT PRIMARY KEY, b TIMESTAMPTZ);
> SHOW COLUMNS FROM timestamps;
+-------------+--------------------------+-------------+----------------+-----------------------+-------------+
| column_name | data_type | is_nullable | column_default | generation_expression | indices |
+-------------+--------------------------+-------------+----------------+-----------------------+-------------+
| a | INT | false | NULL | | {"primary"} |
| b | TIMESTAMP WITH TIME ZONE | true | NULL | | {} |
+-------------+--------------------------+-------------+----------------+-----------------------+-------------+
(2 rows)
> INSERT INTO timestamps VALUES (1, TIMESTAMPTZ '2016-03-26 10:10:10-05:00'), (2, TIMESTAMPTZ '2016-03-26');
> SELECT * FROM timestamps;
+---+---------------------------+
| a | b |
+---+---------------------------+
| 1 | 2016-03-26 15:10:10+00:00 |
| 2 | 2016-03-26 00:00:00+00:00 |
+---+---------------------------+
# Note that the first timestamp is UTC-05:00, which is the equivalent of EST.
Supported casting and conversion
TIMESTAMP values can be cast to any of the following data types:
| Type | Details |
|---|---|
DECIMAL |
Converts to number of seconds since the Unix epoch (Jan. 1, 1970). This is a CockroachDB experimental feature which may be changed without notice. |
FLOAT |
Converts to number of seconds since the Unix epoch (Jan. 1, 1970). This is a CockroachDB experimental feature which may be changed without notice. |
TIME |
Converts to the time portion (HH:MM:SS) of the timestamp |
INT |
Converts to number of seconds since the Unix epoch (Jan. 1, 1970). This is a CockroachDB experimental feature which may be changed without notice. |
DATE |
-- |
STRING |
-- |