$Header: /cvsroot/pgpool/pgpool-II/TODO,v 1.18.2.1 2009/08/24 04:36:10 t-ishii Exp $

* General

Subject: [Pgpool-general] Bug when using Pgpool and PQprepare
From: denis@edistar.com
To: pgpool-general@pgfoundry.org
Date: Wed, 26 Aug 2009 18:23:20 +0200

#0  ReadyForQuery (frontend=0x810bb50, backend=0x810b310, send_ready=1)
    at pool_proto_modules.c:1202
#1  0x080586e4 in SimpleForwardToFrontend (kind=69 'E', frontend=0x810bb50,
    backend=0x810b310) at pool_process_query.c:1871
#2  0x08058d58 in SimpleForwardToBackend (kind=66 'B', frontend=0x810bb50,
    backend=0x810b310) at pool_process_query.c:2069
#3  0x08078f61 in ProcessFrontendResponse (frontend=0x810bb50,
    backend=0x810b310) at pool_proto_modules.c:1505
#4  0x080551d2 in pool_process_query (frontend=0x810bb50, backend=0x810b310,
    connection_reuse=0, first_ready_for_query_received=0)
    at pool_process_query.c:308
#5  0x0804d935 in do_child (unix_fd=3, inet_fd=4) at child.c:427
#6  0x0804b62a in fork_a_child (unix_fd=3, inet_fd=4, id=0) at main.c:836
#7  0x0804cc93 in reaper () at main.c:1625
#8  0x0804d11d in pool_sleep (second=0) at main.c:1824
#9  0x0804ab73 in main (argc=6, argv=0xbf869a04) at main.c:588
(gdb)

Preparing the statement...
To backend> Msg P
To backend> ""
To backend> "INSERT INTO test_table (a) VALUES ($1)"
To backend (2#)> 1
To backend (4#)> 0
To backend> Msg complete, length 51
To backend> Msg S
To backend> Msg complete, length 5

To backend> Msg E
To backend> ""
To backend (4#)> 0
To backend> Msg complete, length 10
To backend> Msg S
To backend> Msg complete, length 5
From backend> E
From backend (#4)> 88
From backend> S
From backend> "ERROR"
From backend> C
From backend> "22P02"
From backend> M
From backend> "invalid input syntax for integer: "123.5""
From backend> F
From backend> "numutils.c"
From backend> L
From backend> "106"
From backend> R
From backend> "pg_atoi"
From backend>  
From backend> Z
From backend (#4)> 5
From backend> Z
From backend (#4)> 5
From backend> E
From backend> n
From backend (#4)> 4
message type 0x6e arrived from server while idle (n)
From backend> I
From backend (#4)> 4
message type 0x49 arrived from server while idle (I: EmptyQueryResponse)
From backend> Z
From backend (#4)> 5
message type 0x5a arrived from server while idle (Z)
Error executing the statement...

Error Message:ERROR:  invalid input syntax for integer: "123.5"

PostgreSQLの場合

./a.out 
To backend> Msg Q
To backend> "begin;"
To backend> Msg complete, length 12
From backend> C
From backend (#4)> 10
From backend> "BEGIN"
From backend> Z
From backend (#4)> 5
From backend> Z
From backend (#4)> 5
From backend> T
Preparing the statement...
To backend> Msg P
To backend> ""
To backend> "INSERT INTO test_table (a) VALUES ($1)"
To backend (2#)> 1
To backend (4#)> 0
To backend> Msg complete, length 51
To backend> Msg S
To backend> Msg complete, length 5
From backend> 1
From backend (#4)> 4
From backend> Z
From backend (#4)> 5
From backend> Z
From backend (#4)> 5
From backend> T
Executing the statement...
To backend> Msg B
To backend> ""
To backend> ""
To backend (2#)> 0
To backend (2#)> 1
To backend (4#)> 5
To backend> 123.5
To backend (2#)> 1
To backend (2#)> 0
To backend> Msg complete, length 24
To backend> Msg D
To backend> P
To backend> ""
To backend> Msg complete, length 7
To backend> Msg E
To backend> ""
To backend (4#)> 0
To backend> Msg complete, length 10
To backend> Msg S
To backend> Msg complete, length 5
From backend> E
From backend (#4)> 88
From backend> S
From backend> "ERROR"
From backend> C
From backend> "22P02"
From backend> M
From backend> "invalid input syntax for integer: "123.5""
From backend> F
From backend> "numutils.c"
From backend> L
From backend> "106"
From backend> R
From backend> "pg_atoi"
From backend>  
From backend> Z
From backend (#4)> 5
From backend> Z
From backend (#4)> 5
From backend> E
Error executing the statement...

Error Message:ERROR:  invalid input syntax for integer: "123.5"
To backend> Msg X
To backend> Msg complete, length 5


- Add backend id to statement log so that we can know if pgpool does
  replication correctly

- Show PostgreSQL backend process ids in process status

- Prepare for changing postgresql.conf directives which produce 'S'
  message. Othewise we get:

  pool_process_query: 1 th kind S does not match with master or majority
  connection kind C

  ERROR: pid 26122: kind mismatch
  among backends. Possible last query was: "UPDATE branches SET bbalance
  = bbalance + -3820 WHERE bid = 1;" kind details are: 0[C] 1[S]

  It seems PostgreSQL sends following parameter status at the *first* pgpool.conf reload only.

2009-02-23 23:06:21 LOG:   pid 5611: name: is_superuser value: on
2009-02-23 23:06:31 LOG:   pid 5627: name: DateStyle value: ISO, MDY
2009-02-23 23:06:31 LOG:   pid 5626: name: DateStyle value: ISO, MDY
2009-02-23 23:06:31 LOG:   pid 5622: name: DateStyle value: ISO, MDY

  (this item was resolved in 2.2)

- drop table should be in a transactin block? It is judged here:
  (this item was resolved in 2.2)

POOL_STATUS start_internal_transaction(POOL_CONNECTION_POOL *backend, Node *node)
{
	int i;

	/* if we are not in a transaction block,
	 * start a new transaction
	 */
	if (TSTATE(backend) == 'I' &&
		(IsA(node, InsertStmt) || IsA(node, UpdateStmt) ||
		 IsA(node, DeleteStmt) || IsA(node, SelectStmt)))

  example session log:

2009-01-09 00:22:20 JST t-ishii test 853 LOG:  statement: begin;
2009-01-09 00:22:23 JST t-ishii test 853 LOG:  statement: lock table t1;
2009-01-09 00:22:23 JST t-ishii test 853 LOG:  unexpected EOF on client connection
2009-01-09 00:22:45 JST t-ishii test 860 LOG:  statement: drop table t1;
2009-01-09 00:22:46 JST t-ishii test 860 LOG:  unexpected EOF on client connection
2009-01-09 00:22:49 JST t-ishii test 877 LOG:  statement: drop table t1;
2009-01-09 00:22:49 JST t-ishii test 877 ERROR:  table "t1" does not exist
2009-01-09 00:22:49 JST t-ishii test 877 STATEMENT:  drop table t1;


?????????
2009-01-09 00:22:23 JST t-ishii test 854 LOG:  unexpected EOF on client connection
2009-01-09 00:22:46 JST t-ishii test 861 LOG:  statement: drop table t1;
2009-01-09 00:22:46 JST t-ishii test 861 ERROR:  cache lookup failed for constraint 1857934
2009-01-09 00:22:46 JST t-ishii test 861 STATEMENT:  drop table t1;
2009-01-09 00:22:46 JST t-ishii test 861 LOG:  could not send data to client: ???????????
2009-01-09 00:22:46 JST t-ishii test 861 LOG:  unexpected EOF on client connection
2009-01-09 00:22:49 JST t-ishii test 878 LOG:  statement: drop table t1;
2009-01-09 00:22:49 JST t-ishii test 878 ERROR:  cache lookup failed for constraint 1857934
2009-01-09 00:22:49 JST t-ishii test 878 STATEMENT:  drop table t1;
2009-01-09 00:25:51 JST t-ishii test 878 LOG:  statement: create table t1(i int);
2009-01-09 00:25:52 JST t-ishii test 878 ERROR:  relation "t1" already exists
2009-01-09 00:25:52 JST t-ishii test 878 STATEMENT:  create table t1(i int);
2009-01-09 00:25:52 JST t-ishii test 878 LOG:  could not send data to client: ???????????
2009-01-09 00:25:52 JST t-ishii test 878 LOG:  unexpected EOF on client connection

- BEGIN; BEGIN; causes:
  (this item was resolved in 2.2)

  ERROR:  kind mismatch among backends 0[N] 1[E]

  detect_error() checks following  NOTICE(ERRROの25001 means /* SET
  TRANSACTION ISOLATION LEVEL must be called before any query */)

  WARNING:  25001: there is already a transaction in progress

  this will send an error query to abort a transaction.

- regression failres:

     triggers             ... FAILED
test sanity_check         ... FAILED
     portals              ... FAILED
test misc                 ... FAILED
     plpgsql              ... FAILED
     largeobject          ... FAILED
test tablespace           ... FAILED

========================
 7 of 114 tests failed. 
========================

  this happens when replication true, insert_lock true, replicate_select false,
  load_balance false.

  if replicate_select is true, prepared_xacts fails(because \d fails)
  and prepared transactio remain, which keep a lock on pg_class in
  access share mode. And alter table pg_class cannot obtain exclusive
  lock, which causes all SELECTs suspend and regression cannot contiunue.

- Allow client encoding conversion. This was possible in pgpool-I

- Allow special comment such as "/* STRICT */". This was possible in pgpool-I

- Allow multi statement

- Sometimes query is sent to a DB node despite its weight is 0

- Avoid cross pgpool process deadlock situation. This is a long
  standing problem since pgpool-II was born (pgpool-I avoids this by
  setting timeout)

- Allow to stop PostgeSQL from pgpoolAdmin to make the on-line
  recovery more convenient. This requires something like
  pgpool_remote_stop to be specified in pgpool.conf.

- If DISCARD ALL is specified in the reset_query_list and transaction
  is not closed when client disconnects, automatically issue ABORT
  before issuing DISCARD ALL

- Add SSL support

- Allow to specify queries issued when starting sessions

- Audit functionality?

- Make accept queue

- Graceful shutdown, attach, detach

* Query handling

- Enhance DROP DATABASE handling (not disconnect all idle connections)

* Replication

- Allow per table replication

- Allow per session level and query level load balancing

- Allow replication of SEQUENCE

- Allow replication of OID

- Allow to specify functions to be replicated other than nextval(), setval()

* On line recovery

- Allow recovery_1st_stage_command to get PostgreSQL listen port,
  database cluster directory etc. info

* Query cache

- Cache invalidation

* Parallel query

- Performance enhance for more complex queries

- Allow to handle transaction

- Allow to handle extended queries

- process alias in FROM clause

db=# select * from data1 as d1 inner join data2 as d2 on d1.id=d2.id;
ERROR:  sql error
DETAIL:  ERROR:  missing FROM-clause entry for table "d1"
LINE 1: SELECT pool_parallel("SELECT d1.id, d1.aaaa, d1.bbbb...
               ^
2008-03-11 10:28:17 LOG:   pid 6186: statement: SELECT pool_parallel("SELECT d1.id, d1.aaaa, d1.bbbb, a.cccc FROM data1")

- process USING clause in JOIN

* Docs

- Write libpcp API docs