1 files changed, 14 insertions, 23 deletions
diff --git a/src/test/regress/sql/btree_index.sql b/src/test/regress/sql/btree_index.sql
index 2b087be796c..19fbfa8b720 100644
--- a/src/test/regress/sql/btree_index.sql
+++ b/src/test/regress/sql/btree_index.sql
@@ -84,32 +84,23 @@ reset enable_indexscan;
 reset enable_bitmapscan;
 
 --
--- Test B-tree page deletion. In particular, deleting a non-leaf page.
+-- Test B-tree fast path (cache rightmost leaf page) optimization.
 --
 
--- First create a tree that's at least four levels deep. The text inserted
--- is long and poorly compressible. That way only a few index tuples fit on
--- each page, allowing us to get a tall tree with fewer pages.
-create table btree_tall_tbl(id int4, t text);
-create index btree_tall_idx on btree_tall_tbl (id, t) with (fillfactor = 10);
-insert into btree_tall_tbl
-  select g, g::text || '_' ||
-          (select string_agg(md5(i::text), '_') from generate_series(1, 50) i)
-from generate_series(1, 100) g;
-
--- Delete most entries, and vacuum. This causes page deletions.
-delete from btree_tall_tbl where id < 950;
-vacuum btree_tall_tbl;
-
+-- First create a tree that's at least three levels deep (i.e. has one level
+-- between the root and leaf levels). The text inserted is long.  It won't be
+-- compressed because we use plain storage in the table.  Only a few index
+-- tuples fit on each internal page, allowing us to get a tall tree with few
+-- pages.  (A tall tree is required to trigger caching.)
 --
--- Test B-tree insertion with a metapage update (XLOG_BTREE_INSERT_META
--- WAL record type). This happens when a "fast root" page is split.
---
-
--- The vacuum above should've turned the leaf page into a fast root. We just
--- need to insert some rows to cause the fast root page to split.
-insert into btree_tall_tbl (id, t)
-  select g, repeat('x', 100) from generate_series(1, 500) g;
+-- The text column must be the leading column in the index, since suffix
+-- truncation would otherwise truncate tuples on internal pages, leaving us
+-- with a short tree.
+create table btree_tall_tbl(id int4, t text);
+alter table btree_tall_tbl alter COLUMN t set storage plain;
+create index btree_tall_idx on btree_tall_tbl (t, id) with (fillfactor = 10);
+insert into btree_tall_tbl select g, repeat('x', 250)
+from generate_series(1, 130) g;
 
 --
 -- Test vacuum_cleanup_index_scale_factor