postgres 9.5 FDW变化

最新推荐文章于 2023-03-29 11:00:34 发布

转载最新推荐文章于 2023-03-29 11:00:34 发布 · 72 阅读

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原文链接：http://www.cnblogs.com/sangli/p/5437148.html

本文对比了PostgreSQL 9.4与9.5版本中关于foreign data wrapper (FDW)的两个关键函数create_foreignscan_path及make_foreignscan的变化。9.5版本在create_foreignscan_path中新增了一个Path*fdw_outerpath参数，在make_foreignscan中增加了3个参数，包括List*fdw_scan_tlist、List*fdw_recheck_quals和Plan*outer_plan。这些改动为使用FDW提供了更多的灵活性。

9.5主要是2个方法有变动:

create_foreignscan_path

extern ForeignPath *create_foreignscan_path(PlannerInfo *root, RelOptInfo *rel,
						double rows, Cost startup_cost, Cost total_cost,
						List *pathkeys,
						Relids required_outer,
						Path *fdw_outerpath,
						List *fdw_private);

9.4比9.5少了个Path *fdw_outerpath

extern ForeignPath *create_foreignscan_path(PlannerInfo *root, RelOptInfo *rel,
						double rows, Cost startup_cost, Cost total_cost,
						List *pathkeys,
						Relids required_outer,
						List *fdw_private);

make_foreignscan

这个函数在9.5中添加了3个参数:

extern ForeignScan *make_foreignscan(List *qptlist, List *qpqual,
				 Index scanrelid, List *fdw_exprs, List *fdw_private,
				 List *fdw_scan_tlist, List *fdw_recheck_quals,
				 Plan *outer_plan);

9.4中的make_foreignscan

extern ForeignScan *make_foreignscan(List *qptlist, List *qpqual,
				 Index scanrelid, List *fdw_exprs, List *fdw_private);

在接口fdwroutine->GetForeignPlan中需要添加一个Plan *outer_plan

这样就能快乐的在9.5上面玩耍fdw了

转载于:https://www.cnblogs.com/sangli/p/5437148.html