This topic describes the limits of search index.

Mapping

Item Maximum value Description
Number of index fields 500 The maximum number of fields that can be indexed.
Array length 256 The maximum number of elements in an array.
Number of fields for EnableSortAndAgg 100 The maximum number of sort and aggregate fields.
Number of nested levels 5 A maximum of five levels can be nested.
Number of child rows in nested fields 256 The maximum number of rows that can be nested within the nested fields.
Number of nested fields 25 The maximum number of fields that can be nested.
Total length of primary key columns 1000 Byte The total length of all primary key columns of each row can be up to 1,000 bytes.
Total length of strings in primary key columns 1000 Byte The total length of strings in all primary key columns of each row can be a maximum of 1,000 bytes.
Total length of strings (indexed as KEYWORD) in all attribute columns 4 KB None.
Total length of strings (indexed as TEXT) in all attribute columns 2 MB Same as the length limit on attribute columns in tables.
String length of a query that contains wildcards 10 The string of a query that contains wildcards can be up to 10 characters in length.

Search

Category Item Maximum value Description
General limits offset+limit 10000 To query more than 10,000 rows, you must specify the next_token parameter.
limit 100
  • When you call the SearchIndex operation to query the data of a specified column, you can set the limit parameter to a value up to 1000 if the search index contains the data.
  • If your business requirements are not met due to the limit, submit a ticket.
timeout 10s None.
CU 100000
  • This limit does not apply to scanning and analysis requests.
  • If your business requirements are not met due to the limit, submit a ticket.
QPS 100000
  • The upper limit for lightweight transaction processing is 100,000 queries per second (QPS).
  • If your business requirements are not met due to the limit, submit a ticket.
Aggregation Number of Aggregations at the same level 5 The number of Aggregations is recalculated each time you add a new Aggregation to SubGroupBy.
Number of GroupBys at the same level 5 The number of GroupBys is recalculated each time you add a new GroupBy to SubGroupBy.
Number of nested levels for a GroupBy 3 The root GroupBy is also calculated as a nested level.
Filters in a GroupByFilter 10 None.
Number of groups returned by a GroupByField 2000 None.
Number of Ranges in a GroupByRange 100 None.
Number of Ranges in a GroupByGeodistance 10 None.

ParallelScan

Category Item Description
General limits offset+limit You cannot specify the the offset and limit parameters for paging when you use parallel scan. Returned results are sequentially displayed.
limit The maximum value is 2000.
CU Unlimited.
QPS Unlimited.
Maximum concurrent tasks The value of MaxParallel in the response to the ComputeSplits operation.

Index

Item Maximum value Description
Rate 50,000 rows/s
  • When data is written to a table for the first time or when a large amount of data is required to be written in a short span of time, it takes several minutes for Tablestore to perform load balancing.
  • The rate of indexing based on the TEXT field is limited to 10,000 rows per second because this indexing consumes more CPU resources for tokenization.
  • If your business requirements are not met due to the limit, submit a ticket.
Synchronization latency 10s
  • The value is smaller than 10 seconds when the writing rate is steady.
  • The synchronization latency is within one minute in most cases.
  • It takes up to one minute to initialize a new index.
Number of rows 20 billion If your business requirements are not met due to the limit, submit a ticket.
Total size 10 TB If your business requirements are not met due to the limit, submit a ticket.

Additional limits

Item Value
Supported region China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou-Beijing Winter Olympics), China (Shenzhen), China (Hong Kong), Singapore, US (Silicon Valley), US (Virginia), and India (Mumbai)
Region to support Australia (Sydney) and UK (London)
Note If your business requirements are not met due to the limit, submit a ticket at the Alibaba Cloud official website. Describe the scenario, items, requirements, and reasons in the ticket. Your requirements will be taken into consideration during future development.