On Tue, Feb 26, 2019 at 10:48 PM Walter Cai <wal...@cs.washington.edu> wrote: > > I'm currently using a (very rough) scheme to retrieve relation names from a > PlannerInfo, and a RelOptInfo struct: > > PlannerInfo *root > RelOptInfo *inner_rel > > //... > > RangeTblEntry *rte; > int x = -1; > while ((x = bms_next_member(inner_rel->relids, x)) >= 0) > { > rte = root->simple_rte_array[x]; > if (rte->rtekind == RTE_RELATION) > { > char *rel_name = get_rel_name(rte->relid); > // do stuff... > } > } > > However, I now realize it would be better to access aliases as they appear in > the SQL query. For instance, if the query contains "... FROM rel_name AS > rel_alias ..." I would like to retrieve `rel_alias` instead of `rel_name`. > > Is it possible to derive the alias in a similar way?
You can use rte->eref->aliasname, which will contain the alias is one was provided, otherwise the original name. You can see RangeTblEntry comment in include/nodes/parsenodes.h for more details.