Date and timestamp format masks follow Java SimpleDateFormat.
See the Java 21 SimpleDateFormat documentation for the full pattern language.
| Letter | Date or Time Component | Presentation | Examples |
|---|---|---|---|
G |
Era designator |
Text |
AD |
y |
Year |
Year |
1996; 96 |
Y |
Week year |
Year |
2009; 09 |
M |
Month in year |
Month |
July; Jul; 07 |
w |
Week in year |
Number |
27 |
W |
Week in month |
Number |
2 |
D |
Day in year |
Number |
189 |
d |
Day in month |
Number |
10 |
F |
Day of week in month |
Number |
2 |
E |
Day name in week |
Text |
Tuesday; Tue |
u |
Day number of week (1 = Monday) |
Number |
1 |
a |
Am/pm marker |
Text |
PM |
H |
Hour in day (0-23) |
Number |
0 |
k |
Hour in day (1-24) |
Number |
24 |
K |
Hour in am/pm (0-11) |
Number |
0 |
h |
Hour in am/pm (1-12) |
Number |
12 |
m |
Minute in hour |
Number |
30 |
s |
Second in minute |
Number |
55 |
S |
Millisecond |
Number |
978 |
z |
Time zone |
General time zone |
Pacific Standard Time; PST; GMT-08:00 |
Z |
Time zone |
RFC 822 time zone |
-0800 |
X |
Time zone |
ISO 8601 time zone |
-08; -0800; -08:00 |
A Date value has millisecond precision.
A Timestamp value can carry nanoseconds; the format mask still uses the SimpleDateFormat letters above, so only milliseconds (S) are expressed in the mask.
See Data types for how Timestamp conversions work.
z, Z and X put a time zone or offset in the string.
Without them, Hop reads and writes wall-clock time in the field’s Date Time Zone (or the JVM default).
That is where daylight-saving gaps and overlaps show up.
See String to Date and Date to String.