Re: current version: [PATCHES] Patch - Have psql show current values
Dhanaraj M <[EMAIL PROTECTED]> writes: > However, it was not possible to display the seq. value using this. > Hence, I made a small change in the currval() function, so that it > retrieves the last_value > even if the the value is not cached. Breaking currval()'s semantics is not an acceptable solution for this. The best, fully backward compatible solution is for psql to issue "SELECT last_value FROM " queries to get the values. This might be a bit tricky to wedge into the structure of describe.c, but I don't see any fundamental reason why it can't be done. regards, tom lane ---(end of broadcast)--- TIP 4: Have you searched our list archives? http://archives.postgresql.org
Re: current version: [PATCHES] Patch - Have psql show current values
Bruce Momjian wrote:
I am thinking we just add another column to the \d display for sequences
showing the current value.
---
As suggested in the previous mails, I tried to use the following to
display the seq. value.
select last_value from .
However, it was not possible to display the seq. value using this.
Hence, I made a small change in the currval() function, so that it
retrieves the last_value
even if the the value is not cached.
I hope this patch will be more suitable for this issue. Pl. look at the
patch.
Thanks
Dhanaraj
*** ./src/backend/commands/sequence.c.orig Tue May 2 14:51:03 2006
--- ./src/backend/commands/sequence.c Tue May 9 13:52:38 2006
***
*** 605,610
--- 605,612
int64 result;
SeqTable elm;
Relation seqrel;
+ Form_pg_sequence seq;
+ Buffer buf;
/* open and AccessShareLock sequence */
init_sequence(relid, &elm, &seqrel);
***
*** 616,632
errmsg("permission denied for sequence %s",
RelationGetRelationName(seqrel;
! if (elm->increment == 0) /* nextval/read_info were not called */
! ereport(ERROR,
! (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
! errmsg("currval of sequence \"%s\" is not yet defined in this session",
! RelationGetRelationName(seqrel;
! result = elm->last;
! relation_close(seqrel, NoLock);
! PG_RETURN_INT64(result);
}
Datum
--- 618,641
errmsg("permission denied for sequence %s",
RelationGetRelationName(seqrel;
! if ((elm->increment != 0) ||(elm->last != elm->cached)) /* some numbers were cached */
! {
! result = elm->last;
! relation_close(seqrel, NoLock);
! PG_RETURN_INT64(result);
! }
! /* lock page' buffer and read tuple if not cached */
! seq = read_info(elm, seqrel, &buf);
! result = seq->last_value;
! UnlockReleaseBuffer(buf);
! relation_close(seqrel, NoLock);
! seqtab = elm->next;
! free(elm);
!
! PG_RETURN_INT64(result);
}
Datum
*** ./src/bin/psql/describe.c.orig Thu Apr 27 04:45:45 2006
--- ./src/bin/psql/describe.c Tue May 9 16:26:10 2006
***
*** 1480,1485
--- 1480,1488
_("table"), _("view"), _("index"), _("sequence"),
_("special"), _("Type"), _("Owner"));
+ if (showSeq && !showTables)
+ appendPQExpBuffer(&buf,",\n currval(CAST(c.relname AS pg_catalog.text)) as \"%s\"",_("value"));
+
if (showIndexes)
appendPQExpBuffer(&buf,
",\n c2.relname as \"%s\"",
No differences encountered
---(end of broadcast)---
TIP 2: Don't 'kill -9' the postmaster
Re: current version: [PATCHES] Patch - Have psql show current values
I am thinking we just add another column to the \d display for sequences showing the current value. --- Euler Taveira de Oliveira wrote: > Bruce Momjian wrote: > > > What fields do we want to show? Maybe the TODO item is not needed. Is > > this all we want to show? > > > IRC what we want is something like this. > > regression=# \d abc >Sequence "public.abc" > Column| Type > --+- > sequence_name | abc > last_value| 1 > increment_by | 1 > max_value | 9223372036854775807 > min_value | 1 > cache_value | 1 > log_cnt | 1 > is_cycled | f > is_called | f > > > Because "\d abc" doesn't show us any important information. > > regression=# \d abc >Sequence "public.abc" > Column | Type > ---+- > sequence_name | name > last_value| bigint > increment_by | bigint > max_value | bigint > min_value | bigint > cache_value | bigint > log_cnt | bigint > is_cycled | boolean > is_called | boolean > > > Last year, I made a patch for this but it was so ugly that I didn't send > to -patches. Maybe Bruce's solution (\x & select * from seq) could be > hardcoded in describe.c. > > -- >Euler Taveira de Oliveira >http://www.timbira.com/ > > ---(end of broadcast)--- > TIP 3: Have you checked our extensive FAQ? > >http://www.postgresql.org/docs/faq > -- Bruce Momjian http://candle.pha.pa.us EnterpriseDBhttp://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
Re: current version: [PATCHES] Patch - Have psql show current values
Bruce Momjian wrote: What fields do we want to show? Maybe the TODO item is not needed. Is this all we want to show? IRC what we want is something like this. regression=# \d abc Sequence "public.abc" Column| Type --+- sequence_name | abc last_value| 1 increment_by | 1 max_value | 9223372036854775807 min_value | 1 cache_value | 1 log_cnt | 1 is_cycled | f is_called | f Because "\d abc" doesn't show us any important information. regression=# \d abc Sequence "public.abc" Column | Type ---+- sequence_name | name last_value| bigint increment_by | bigint max_value | bigint min_value | bigint cache_value | bigint log_cnt | bigint is_cycled | boolean is_called | boolean Last year, I made a patch for this but it was so ugly that I didn't send to -patches. Maybe Bruce's solution (\x & select * from seq) could be hardcoded in describe.c. -- Euler Taveira de Oliveira http://www.timbira.com/ ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
Re: current version: [PATCHES] Patch - Have psql show current values
As Tom asked, why not use seqname.last_value? Looking at your output:
+ if (showSeq && !showTables)
+ appendPQExpBuffer(&buf,
+ ",\n curval(c.oid) as \"%s\""
+ ",\n CASE curvalcheck(c.oid) WHEN '1' THEN '%s'
WHEN '0' THEN '%s' END as \"%s\"",
+ _("value"),_(" ***"),_(""),_("Start from"));
What do you want to show that seqname.last_value doesn't give you?
Curval? I don't see that as useful for a psql display. Now that I look
at the TODO item:
o Have psql show current values for a sequence
It is confusing. It means "the current values" for the sequence, not
"curval" for the sequence. I don't even understand what your function
is returning. Just stick to last_value, though I think
seqname.is_called might be what you were looking for.
What fields do we want to show? Maybe the TODO item is not needed. Is
this all we want to show?
test=> \x
Expanded display is on.
test=> select * from xx;
-[ RECORD 1 ]-+
sequence_name | xx
last_value| 1
increment_by | 1
max_value | 9223372036854775807
min_value | 1
cache_value | 1
log_cnt | 32
is_cycled | f
is_called | t
---
Dhanaraj M wrote:
> Tom Lane wrote:
>
> >Dhanaraj M <[EMAIL PROTECTED]> writes:
> >
> >
> >>sorry for sending the old version in the previous mail . Here I attach
> >>the recent version of the patch file.
> >>
> >>
> >--
> >
> >
> Surely this problem does not require adding any server-side code.
>
> >Something like "select last_value from " would be more appropriate;
> >and it'd have some hope of working with back-version servers.
> >
> >Also, please use something more helpful than "***" as the column
> >header. Your urge to add a footnote to explain it shows that you
> >didn't try hard enough to devise a good header to begin with.
> >
> >[ btw, both fmgroids.h and fmgrtab.c are generated files. Patching
> >them is unnecessary and inappropriate. ]
> >
> --
>
> The existing functions like lastval, currval dont provide the current
> sequence value always.
> They work only if the sequence is already cached (nextval is called
> atleast once for that sequence).
> Changing the internals of lastval/currval will give the solution.
> However, I feel that the functionality change
> may affect the customers who use the current version.
>
> Hence, I am sure that it requires the server side change. There are two
> options here
> 1. Modifying the exisitng functions (or) 2. adding new functions
>
>
> Thanks for your review
> Dhanaraj
>
>
>
> ---(end of broadcast)---
> TIP 5: don't forget to increase your free space map settings
>
--
Bruce Momjian http://candle.pha.pa.us
EnterpriseDBhttp://www.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +
Dhanaraj M wrote:
> Tom Lane wrote:
>
> >Dhanaraj M <[EMAIL PROTECTED]> writes:
> >
> >
> >>sorry for sending the old version in the previous mail . Here I attach
> >>the recent version of the patch file.
> >>
> >>
> >--
> >
> >
> Surely this problem does not require adding any server-side code.
>
> >Something like "select last_value from " would be more appropriate;
> >and it'd have some hope of working with back-version servers.
> >
> >Also, please use something more helpful than "***" as the column
> >header. Your urge to add a footnote to explain it shows that you
> >didn't try hard enough to devise a good header to begin with.
> >
> >[ btw, both fmgroids.h and fmgrtab.c are generated files. Patching
> >them is unnecessary and inappropriate. ]
> >
> --
>
> The existing functions like lastval, currval dont provide the current
> sequence value always.
> They work only if the sequence is already cached (nextval is called
> atleast once for that sequence).
> Changing the internals of lastval/currval will give the solution.
> However, I feel that the functionality change
> may affect the customers who use the current version.
>
> Hence, I am sure that it requires the server side change. There are two
> options here
> 1. Modifying the exisitng functions (or) 2. adding new functions
>
>
> Thanks for your review
> Dhanaraj
>
>
>
> ---(end of broadcast)---
> TIP 5: don't forget to increase your free space map settings
>
--
Bruce Momjian http://candle.pha.pa.us
EnterpriseDBhttp://www.enterpr
Re: current version: [PATCHES] Patch - Have psql show current values
Tom Lane wrote: Dhanaraj M <[EMAIL PROTECTED]> writes: sorry for sending the old version in the previous mail . Here I attach the recent version of the patch file. -- Surely this problem does not require adding any server-side code. Something like "select last_value from " would be more appropriate; and it'd have some hope of working with back-version servers. Also, please use something more helpful than "***" as the column header. Your urge to add a footnote to explain it shows that you didn't try hard enough to devise a good header to begin with. [ btw, both fmgroids.h and fmgrtab.c are generated files. Patching them is unnecessary and inappropriate. ] -- The existing functions like lastval, currval dont provide the current sequence value always. They work only if the sequence is already cached (nextval is called atleast once for that sequence). Changing the internals of lastval/currval will give the solution. However, I feel that the functionality change may affect the customers who use the current version. Hence, I am sure that it requires the server side change. There are two options here 1. Modifying the exisitng functions (or) 2. adding new functions Thanks for your review Dhanaraj ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
Re: current version: [PATCHES] Patch - Have psql show current values for a sequence]
Dhanaraj M <[EMAIL PROTECTED]> writes: > sorry for sending the old version in the previous mail . Here I attach > the recent version of the patch file. Surely this problem does not require adding any server-side code. Something like "select last_value from " would be more appropriate; and it'd have some hope of working with back-version servers. Also, please use something more helpful than "***" as the column header. Your urge to add a footnote to explain it shows that you didn't try hard enough to devise a good header to begin with. [ btw, both fmgroids.h and fmgrtab.c are generated files. Patching them is unnecessary and inappropriate. ] regards, tom lane ---(end of broadcast)--- TIP 4: Have you searched our list archives? http://archives.postgresql.org
