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- Aggregation Pipeline Limits
Aggregation Pipeline Limits¶
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Aggregation operations with the aggregate
command have the
following limitations.
Type Restrictions¶
The aggregation pipeline cannot operate
on values of the following types: Symbol
, MinKey
, MaxKey
,
DBRef
, Code
, and CodeWScope
.
Changed in version 2.4: Removed restriction on Binary
type data. In MongoDB 2.2, the pipeline
could not operate on Binary
type data.
Result Size Restrictions¶
Output from the pipeline cannot exceed the BSON Document Size
limit, which is currently 16 megabytes. If the result set exceeds this
limit, the aggregate
command produces an error.
Memory Restrictions¶
If any single aggregation operation consumes more than 10 percent of system RAM, the operation will produce an error.
Cumulative operators, such as $sort
and $group
,
require access to the entire input set before they can produce any
output. These operators log a warning if the cumulative operator
consumes 5% or more of the physical memory on the host. Like any
aggregation operation, these operators produce an error if they consume
10% or more of the physical memory on the host. See the
$sort
and $group
reference pages for details on
their specific memory requirements and use.