hcq/postgresql
1
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2026-02-18 20:36:58 +08:00
Code Issues Packages Projects Releases Wiki Activity

Add a new system view, pg_cursors, that displays the currently available

Browse Source 
cursors. Patch from Joachim Wieland, review and ediorialization by Neil
Conway. The view lists cursors defined by DECLARE CURSOR, using SPI, or
via the Bind message of the frontend/backend protocol. This means the
view does not list the unnamed portal or the portal created to implement
EXECUTE. Because we do list SPI portals, there might be more rows in
this view than you might expect if you are using SPI implicitly (e.g.
via a procedural language).

Per recent discussion on -hackers, the query string included in the
view for cursors defined by DECLARE CURSOR is based on
debug_query_string. That means it is not accurate if multiple queries
separated by semicolons are submitted as one query string. However,
there doesn't seem a trivial fix for that: debug_query_string
is better than nothing. I also changed SPI_cursor_open() to include
the source text for the portal it creates: AFAICS there is no reason
not to do this.

Update the documentation and regression tests, bump the catversion.
This commit is contained in:
Neil Conway
2006-01-18 06:49:30 +00:00
parent 558bc2584d
commit 33e06ebccb
17 changed files with 388 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
src/test/regress/sql/portals.sql
View File

@ -168,8 +168,14 @@ CLOSE foo12;
-- leave some cursors open, to test that auto-close works.
-- record this in the system view as well (don't query the time field there
-- however)
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
END;
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
--
-- NO SCROLL disallows backward fetching
--
@ -188,6 +194,9 @@ END;
-- Cursors outside transaction blocks
--
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
BEGIN;
DECLARE foo25 SCROLL CURSOR WITH HOLD FOR SELECT * FROM tenk2;
@ -204,6 +213,8 @@ FETCH BACKWARD FROM foo25;
FETCH ABSOLUTE -1 FROM foo25;
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
CLOSE foo25;
--
@ -278,3 +289,17 @@ fetch all from c2;
drop function count_tt1_v();
drop function count_tt1_s();
-- Create a cursor with the BINARY option and check the pg_cursors view
BEGIN;
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
DECLARE bc BINARY CURSOR FOR SELECT * FROM tenk1;
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
ROLLBACK;
-- We should not see the portal that is created internally to
-- implement EXECUTE in pg_cursors
PREPARE cprep AS
SELECT name, statement, is_holdable, is_binary, is_scrollable FROM pg_cursors;
EXECUTE cprep;