Add new session variable "tidb_opt_partial_ordered_index_for_topn" by elsa0520 · Pull Request #21318 · pingcap/docs-cn

elsa0520 · 2026-02-05T04:31:54Z

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system-variables.md

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system-variables.md

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qw4990 · 2026-02-26T04:24:10Z

system-variables.md

+    ```sql
+    > SET SESSION tidb_opt_partial_ordered_index_for_topn = 'COST';
+
+    > EXPLAIN FORMAT='brief' SELECT /*+ use_index(t_varchar, idx_name_prefix) */ *


Could we also add the create-table statement here? Otherwise, we don't know what this index idx_name_prefix looks like.

added in 14be16f.

system-variables.md

ti-chi-bot · 2026-04-03T03:47:37Z

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2026-02-25 07:49:17.816649991 +0000 UTC m=+254830.331444600: ☑️ agreed by qiancai.
2026-04-03 03:47:36.257464558 +0000 UTC m=+496061.462824615: ☑️ agreed by Oreoxmt.

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Add new session variable "tidb_opt_partial_ordered_index_for_topn"

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feat(dqp): support partial ordered topn set_var and external hints hawkingrei/shiro#116

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Add new session variable "tidb_opt_partial_ordered_index_for_topn" pingcap/docs#22495

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update tidb.net and asktug links pingcap/docs#22496

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elsa0520 commented Feb 5, 2026 •

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