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@@ -244,9 +244,18 @@ determined and is given a value of -1 to indicate this.
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==== Order
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The order of the buckets can be customized by setting the `order` parameter. By default, the buckets are ordered by
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-their `doc_count` descending. It is also possible to change this behaviour as follows:
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+their `doc_count` descending. It is possible to change this behaviour as documented below:
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-Ordering the buckets by their `doc_count` in an ascending manner:
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+WARNING: Sorting by ascending `_count` or by sub aggregation is discouraged as it increases the
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+<<search-aggregations-bucket-terms-aggregation-approximate-counts,error>> on document counts.
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+It is fine when a single shard is queried, or when the field that is being aggregated was used
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+as a routing key at index time: in these cases results will be accurate since shards have disjoint
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+values. However otherwise, errors are unbounded. One particular case that could still be useful
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+is sorting by <<search-aggregations-metrics-min-aggregation,`min`>> or
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+<<search-aggregations-metrics-max-aggregation,`max`>> aggregation: counts will not be accurate
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+but at least the top buckets will be correctly picked.
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+
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+Ordering the buckets by their doc `_count` in an ascending manner:
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[source,js]
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--------------------------------------------------
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@@ -317,14 +326,15 @@ Ordering the buckets by multi value metrics sub-aggregation (identified by the a
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}
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--------------------------------------------------
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-WARNING: Sorting by ascending `_count` or by sub aggregation is discouraged as it increases the
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-<<search-aggregations-bucket-terms-aggregation-approximate-counts,error>> on document counts.
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-It is fine when a single shard is queried, or when the field that is being aggregated was used
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-as a routing key at index time: in these cases results will be accurate since shards have disjoint
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-values. However otherwise, errors are unbounded. One particular case that could still be useful
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-is sorting by <<search-aggregations-metrics-min-aggregation,`min`>> or
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-<<search-aggregations-metrics-max-aggregation,`max`>> aggregation: counts will not be accurate
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-but at least the top buckets will be correctly picked.
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+.Pipeline aggs cannot be used for sorting
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+[INFO]
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+=======================================
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+
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+<<search-aggregations-pipeline,Pipeline aggregations>> are run during the
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+reduce phase after all other aggregations have already completed. For this
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+reason, they cannot be used for ordering.
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+
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+=======================================
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It is also possible to order the buckets based on a "deeper" aggregation in the hierarchy. This is supported as long
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as the aggregations path are of a single-bucket type, where the last aggregation in the path may either be a single-bucket
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Clinton Gormley