<s>
Amazon	B-Application
DocumentDB	I-Application
is	O
a	O
managed	O
proprietary	B-Application
NoSQL	B-General_Concept
database	O
service	O
that	O
supports	O
document	O
data	O
structures	O
,	O
with	O
some	O
compatibility	O
with	O
MongoDB	B-Application
version	O
3.6	O
(	O
released	O
by	O
MongoDB	B-Application
in	O
2017	O
)	O
and	O
version	O
4.0	O
(	O
released	O
by	O
MongoDB	B-Application
in	O
2018	O
)	O
.	O
</s>
<s>
As	O
a	O
document	B-General_Concept
database	I-General_Concept
,	O
Amazon	B-Application
DocumentDB	I-Application
can	O
store	O
,	O
query	O
,	O
and	O
index	B-Data_Structure
JSON	B-General_Concept
data	O
.	O
</s>
<s>
It	O
is	O
available	O
on	O
Amazon	B-Application
Web	I-Application
Services	I-Application
.	O
</s>
<s>
As	O
of	O
March	O
2023	O
,	O
AWS	B-Application
introduced	O
some	O
compliance	O
with	O
MongoDB	B-Application
5.0	O
,	O
but	O
lacks	O
time	O
series	O
collection	O
support	O
.	O
</s>
<s>
A	O
document	B-General_Concept
database	I-General_Concept
natively	O
stores	O
JSON	B-General_Concept
data	O
.	O
</s>
<s>
DocumentDB	B-Application
provides	O
single	O
document	O
lookups	O
,	O
index	B-Data_Structure
scans	O
,	O
regular	B-Language
expression	I-Language
queries	O
,	O
and	O
aggregations	O
.	O
</s>
<s>
It	O
can	O
create	O
single	O
field	O
,	O
compound	O
,	O
and	O
multi-key	B-Application
indexes	O
to	O
improve	O
the	O
performance	O
of	O
query	O
patterns	O
.	O
</s>
<s>
Reads	O
from	O
the	O
indexes	O
on	O
the	O
primary	O
instance	O
are	O
read-after-write	B-Application
consistent	O
and	O
users	O
can	O
delete	O
or	O
create	O
new	O
indexes	O
at	O
any	O
time	O
.	O
</s>
<s>
DocumentDB	B-Application
was	O
an	O
enhancement	O
to	O
the	O
Amazon	B-Application
Aurora	O
relational	O
database	O
system	O
,	O
specifically	O
the	O
PostgreSQL-compatible	O
edition	O
.	O
</s>
<s>
Amazon	B-Application
DocumentDB	I-Application
,	O
through	O
Aurora	O
PostgreSQL	O
,	O
uses	O
the	O
Aurora	O
Storage	O
Engine	O
,	O
originally	O
built	O
for	O
the	O
MySQL	O
relational	O
database	O
.	O
</s>
<s>
This	O
storage	O
engine	O
is	O
distributed	B-Application
,	O
fault-tolerant	B-General_Concept
,	O
self-healing	B-General_Concept
,	O
and	O
durable	B-General_Concept
,	O
which	O
it	O
maintains	O
by	O
replicating	B-Architecture
data	I-Architecture
six	O
ways	O
across	O
three	O
AWS	B-Application
Availability	O
Zones	O
(	O
AZs	O
)	O
.	O
</s>
<s>
Amazon	B-Application
DocumentDB	I-Application
databases	O
cannot	O
span	O
AWS	B-Application
Regions	O
or	O
span	O
cloud	O
providers	O
,	O
nor	O
can	O
Amazon	B-Application
DocumentDB	I-Application
run	O
on-premises	O
.	O
</s>
<s>
The	O
system	O
can	O
support	O
up	O
to	O
15	O
low-latency	O
readable	O
replicas	B-General_Concept
and	O
continuously	O
backs	O
up	O
all	O
changes	O
to	O
Amazon	B-Application
S3	O
.	O
</s>
