This topic describes the limits on search indexes.

Mapping

Item Maximum value Description
Number of indexed fields 500 The number of fields that can be indexed.
Array length 256 The maximum number of elements in an array.
Number of fields for which EnableSortAndAgg is set to true 100 The number of fields that can be sorted and aggregated.
Number of nested levels 5 Up to five levels can be nested.
Number of child rows in a nested field 256 The maximum number of child rows that are contained in a nested field.
Number of nested fields 25 The number of child fields that can be nested.
Total length of primary key columns 1000 Byte The total length of all primary key columns cannot exceed 1,000 bytes.
Length of the value in the primary key column of the STRING type 1000 Byte To index a primary key column of the STRING type, the column value cannot exceed 1,000 bytes in length.
Length of an attribute column of the STRING type in a table if you want to index the column as KEYWORD 4 KB None.
Length of an attribute column of the STRING type in a table if you want to index the column as TEXT 2 MB The value is the same as the length limit on an attribute column in a table.
Length of a query string that contains an asterisk (*) 32 The length of a query string that contains an asterisk (*) cannot exceed 32 characters.

Search

Category Item Maximum value Description
General limits offset+limit 10000 To increase the number of returned rows, configure the next_token parameter.
limit 100
  • When you call the Search operation to query data of a specified column, the maximum value of the limit parameter can be increased to 1000 if the data is contained in search indexes.
  • To increase the limit, submit a ticket.
timeout 10s None.
CU 100,000
  • This limit does not take effect for scanning and analysis requests.
  • To increase the limit, submit a ticket.
QPS 100,000
  • The upper limit for lightweight transaction processing is 100,000 queries per second (QPS).
  • To increase the limit, submit a ticket.
Aggregation and GroupBy 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 GroupBys 3 The root GroupBy is calculated as a nested level.
Number of Filters in GroupByFilter 10 None.
Number of groups returned by GroupByField 2,000 None.
Number of Ranges in GroupByRange 100 None.
Number of Ranges in GroupByGeodistance 10 None.

ParallelScan

Category Item Description
General limits offset+limit When you use parallel scan, you cannot configure the offset and limit parameters. The results that are returned are displayed in chronological order.
limit The maximum value is 2,000.
CU None.
QPS None.
Maximum number of concurrent tasks The value of the MaxParallel parameter. You can perform the ComputeSplits operation to obtain the value of the parameter.

Index

Item Maximum value Description
Rate 50,000 rows/s
  • The first time when data is written to a table or when a large volume of data is written in a short period of time, Tablestore balances loads within a few minutes.
  • The rate of indexing TEXT fields is 10,000 rows/s because this process consumes a large number of CPU resources for tokenization.
  • To increase the limit, submit a ticket.
Synchronization latency 3s
  • In most cases, the synchronization latency is approximately three seconds.
  • It takes up to one minute to initialize a new index.
Number of rows 50,000,000,000 To increase the limit, submit a ticket.
Total size 50 TB To increase the limit, submit a ticket.

Additional limits

Search indexes are available in the following regions: China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Shenzhen), China (Hong Kong), Singapore (Singapore), Australia (Sydney), Indonesia (Jarkata), Japan (Tokyo), Germany (Frankfurt), UK (London), US (Silicon Valley), US (Virginia), India (Mumbai), and Philippines (Manila).

Note To use search indexes in a wider range of regions, submit a ticket. When you submit a ticket, you must specify the limits and the limit values. You must also specify the scenarios in which you want to use the new limits and the requirements based on which you want to use the new limits. The requirements that you specify in the ticket are recorded for future development purposes.