tidb: add the join order related variable tidb_opt_join_reorder_through_proj#21587
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Reminiscent wants to merge 1 commit into
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tidb: add the join order related variable tidb_opt_join_reorder_through_proj#21587Reminiscent wants to merge 1 commit into
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[APPROVALNOTIFIER] This PR is NOT APPROVED This pull-request has been approved by: The full list of commands accepted by this bot can be found here. DetailsNeeds approval from an approver in each of these files:Approvers can indicate their approval by writing |
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The changes have already been merged into release-8.5 pingcap/tidb#68295, so the documentation for that branch should be updated accordingly. |
Reminiscent
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Jun 2, 2026
| - 这个变量用来控制 TiDB Join Reorder 算法的选择。当参与 Join Reorder 的节点个数大于该阈值时，TiDB 选择贪心算法，小于该阈值时 TiDB 选择动态规划 (dynamic programming) 算法。 | ||
| - 目前对于 OLTP 的查询，推荐保持默认值。对于 OLAP 的查询，推荐将变量值设为 10~15 来获得 AP 场景下更好的连接顺序。 | ||
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| ### `tidb_opt_join_reorder_through_proj` <span class="version-mark">从 v9.0.0 版本开始引入</span> |
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因为也 pick 到了 v8.5 上的版本，这里需要改成 8.5.x 么
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related to pingcap/tidb#65367
pingcap/tidb#68295 (release-8.5)
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