Rename jsonb_hash_ops to jsonb_path_ops.

There's no longer much pressure to switch the default GIN opclass for
jsonb, but there was still some unhappiness with the name "jsonb_hash_ops",
since hashing is no longer a distinguishing property of that opclass,
and anyway it seems like a relatively minor detail.  At the suggestion of
Heikki Linnakangas, we'll use "jsonb_path_ops" instead; that captures the
important characteristic that each index entry depends on the entire path
from the document root to the indexed value.

Also add a user-facing explanation of the implementation properties of
these two opclasses.

3 files changed, 6 insertions, 6 deletions

diff --git a/src/test/regress/expected/jsonb.out b/src/test/regress/expected/jsonb.out
index c5a7d64ae46..ae7c5068119 100644
--- a/src/test/regress/expected/jsonb.out
+++ b/src/test/regress/expected/jsonb.out
@@ -1685,9 +1685,9 @@ SELECT count(*) FROM testjsonb WHERE j = '{"pos":98, "line":371, "node":"CBA", "
      1
 (1 row)
 
---gin hash
+--gin path opclass
 DROP INDEX jidx;
-CREATE INDEX jidx ON testjsonb USING gin (j jsonb_hash_ops);
+CREATE INDEX jidx ON testjsonb USING gin (j jsonb_path_ops);
 SET enable_seqscan = off;
 SELECT count(*) FROM testjsonb WHERE j @> '{"wait":null}';
  count 
diff --git a/src/test/regress/expected/jsonb_1.out b/src/test/regress/expected/jsonb_1.out
index 0e3ebd161ef..38a95b43f8c 100644
--- a/src/test/regress/expected/jsonb_1.out
+++ b/src/test/regress/expected/jsonb_1.out
@@ -1685,9 +1685,9 @@ SELECT count(*) FROM testjsonb WHERE j = '{"pos":98, "line":371, "node":"CBA", "
      1
 (1 row)
 
---gin hash
+--gin path opclass
 DROP INDEX jidx;
-CREATE INDEX jidx ON testjsonb USING gin (j jsonb_hash_ops);
+CREATE INDEX jidx ON testjsonb USING gin (j jsonb_path_ops);
 SET enable_seqscan = off;
 SELECT count(*) FROM testjsonb WHERE j @> '{"wait":null}';
  count 
diff --git a/src/test/regress/sql/jsonb.sql b/src/test/regress/sql/jsonb.sql
index 3e9048911be..7527925b2cb 100644
--- a/src/test/regress/sql/jsonb.sql
+++ b/src/test/regress/sql/jsonb.sql
@@ -391,9 +391,9 @@ SET enable_seqscan = off;
 SELECT count(*) FROM testjsonb WHERE j > '{"p":1}';
 SELECT count(*) FROM testjsonb WHERE j = '{"pos":98, "line":371, "node":"CBA", "indexed":true}';
 
---gin hash
+--gin path opclass
 DROP INDEX jidx;
-CREATE INDEX jidx ON testjsonb USING gin (j jsonb_hash_ops);
+CREATE INDEX jidx ON testjsonb USING gin (j jsonb_path_ops);
 SET enable_seqscan = off;
 
 SELECT count(*) FROM testjsonb WHERE j @> '{"wait":null}';