Database Reference
In-Depth Information
NOTE
If, for some reason, you need to determine whether an upsert was an insert or an update,
you can always check the result of the update operation:
>>>
>>>
result
=
db
.
foo
.
update
({
'x'
:
15
}, {
'$set'
: {
'y'
:
5
} },
upsert
=
True
)
>>>
>>>
result
[
'updatedExisting'
]
False
>>>
>>>
result
=
db
.
foo
.
update
({
'x'
:
15
}, {
'$set'
: {
'y'
:
6
} },
upsert
=
True
)
>>>
>>>
result
[
'updatedExisting'
]
True
Pre-allocate
To prevent document growth, we'll pre-allocate new documents before the system needs
them. In pre-allocation, we set all values to
0
so that documents don't need to grow to accom-
modate updates. Consider the following function:
def
def
preallocate
(
db
,
dt_utc
,
site
,
page
):
# Get id values
id_daily
=
dt_utc
.
strftime
(
'%Y%m
%d
/'
)
+
site
+
page
id_monthly
=
dt_utc
.
strftime
(
'%Y%m/'
)
+
site
+
page
# Get daily metadata
daily_metadata
=
{
'date'
:
datetime
.
combine
(
dt_utc
.
date
(),
time
.
min
),
'site'
:
site
,
'page'
:
page
}
# Get monthly metadata
monthly_metadata
=
{
'date'
:
daily_m
[
'd'
]
.
replace
(
day
=
1
),
'site'
:
site
,
'page'
:
page
}
# Initial zeros for statistics
daily_zeros
=
[
(
'hourly.
%d
'
%
h
,
0
)
for
for
i
iin
range
(
24
) ]
daily_zeros
+=
[
(
'minute.
%d
.
%d
'
%
(
h
,
m
),
0
)
for
for
h
iin
range
(
24
)
for
for
m
iin
range
(
60
) ]
