Storage and I/O unit of a search service, each holding part of the indexes. Adding partitions increases storage and indexing throughput; the number of search units equals replicas multiplied by partitions.
Also called partition.
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Terms in this definition
- General-purpose v1
The older storage account kind (
Storage), which lacks access tiers, Archive and premium file shares and retires on 13 October 2026. Converting to ZRS requires first upgrading to GPv2, a one-way change.
Related terms
- Autotune
A preview option in Fabric Spark that studies previous runs to pick better values for shuffle partitions, broadcast join threshold and max partition bytes query by query. It's disabled by default (
spark.ms.autotune.enabled), limited to Runtime 1.2, and incompatible with private endpoints and high concurrency mode. - Cross-partition query
Also known as a fan-out query: in Azure Cosmos DB, a query with no partition key filter, which therefore has to visit each physical partition in turn. Each partition visited costs roughly 2.5 RU or more, so these queries consume more request units.
- Degree of copy parallelism
The upper limit on simultaneous read or write threads in a Copy activity, configured separately from intelligent throughput optimisation. With partitioning in use it governs how many partition queries run together, so a value that is too large risks overwhelming the source system.
- Detect data changes
An extra incremental refresh option: nominate a timestamp column, for instance one recording when rows were last modified, and Power BI skips any partition whose latest timestamp hasn't moved since the last run.
- DomainDnsZones
A directory partition through which AD-integrated DNS zones reach all domain controllers in one domain that also run DNS.
- ForestDnsZones
A directory partition through which AD-integrated DNS zones reach all domain controllers across the forest that also run DNS.
- Memory Analyzer
Launch it from a semantic model and this Fabric notebook reports how much memory and storage each table, column, hierarchy, partition and relationship uses, making oversized or high-cardinality columns easy to spot.
- NC
Naming context. Each AD partition (domain, schema, configuration or application) replicates as one unit, for instance when running repadmin /replicate.