public inbox for pgsql-performance@postgresql.org  

help / color / mirror / Atom feed

From: Pavel Stehule <pavel.stehule@gmail.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Philippe BEAUDOIN <phb07@apra.asso.fr>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: proposal: schema variables
Date: Sun, 26 Jan 2020 18:26:16 +0100
Message-ID: <CAFj8pRDxHCt9_fDQ8cu07jB4KzyU1qmzgH9uA1XsPdqvZN-w6A@mail.gmail.com> (raw)
In-Reply-To: <20200121234141.se4v2hygsiy3lffx@development>
References: <CAFj8pRDY+m9OOxfO10R7J0PAkCCauM-TweaTrdsrsLGMb1VbEQ@mail.gmail.com>
	<CAFj8pRAcb+PLKJJOGn7POtcTuH8DaKqZNid-7UvB9_BtgshHEQ@mail.gmail.com>
	<157772317031.1198.14690129684698137065.pgcf@coridan.postgresql.org>
	<CAFj8pRA+SYbegM6f5OTamwhMdsVXB22mbmkscaErrhYge8ji3A@mail.gmail.com>
	<CAFj8pRCAGXK9Wd8FGboFkFyUTWwh0qJUKW0muVAMkAUq6feCdA@mail.gmail.com>
	<20200121234141.se4v2hygsiy3lffx@development>

>
>
> 12) I find it rather suspicious that we make decisions in utility.c
> solely based on commandType (whether it's CMD_UTILITY or not). IMO
> it's pretty strange/ugly that T_LetStmt can be both CMD_UTILITY and
> CMD_PLAN_UTILITY:
>
>      case T_LetStmt:
>          {
>              if (pstmt->commandType == CMD_UTILITY)
>                  doLetStmtReset(pstmt);
>              else
>              {
>                  Assert(pstmt->commandType == CMD_PLAN_UTILITY);
>                  doLetStmtEval(pstmt, params, queryEnv, queryString);
>              }
>
>              if (completionTag)
>                  strcpy(completionTag, "LET");
>          }
>          break;
>
>
>
It looks strange, but it has sense, because the LET stmt supports reset to
default value.

I can write

1. LET var = DEFAULT;
2. LET var = (query);

In first case I have not any query, that I can assign, and in this case the
LET statement is really only UTILITY.

I did comment there

Regards

Pavel




>
>
> regards
>
> --
> Tomas Vondra                  http://www.2ndQuadrant.com
> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>


Attachments:

  [application/gzip] 0001-schema-variables-20200126.patch.gz (64.2K, 3-0001-schema-variables-20200126.patch.gz)
  download

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-performance@postgresql.org
  Cc: pavel.stehule@gmail.com, tomas.vondra@2ndquadrant.com, phb07@apra.asso.fr, pgsql-hackers@lists.postgresql.org
  Subject: Re: proposal: schema variables
  In-Reply-To: <CAFj8pRDxHCt9_fDQ8cu07jB4KzyU1qmzgH9uA1XsPdqvZN-w6A@mail.gmail.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox