Re: [HACKERS] proposal: schema variables

Pavel Stehule <pavel.stehule@gmail.com>

From: Pavel Stehule <pavel.stehule@gmail.com>

To: Pavel Luzanov <p.luzanov@postgrespro.ru>

Cc: "David G. Johnston" <david.g.johnston@gmail.com>, Pavel Golub <pavel@gf.microolap.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>

Date: 2018-03-21T05:24:16Z

Lists: pgsql-hackers, pgsql-performance

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Move WAL sequence code into its own file
- a87987cafca6 19 (unreleased) cited
Add ExplainState argument to pg_plan_query() and planner().
- c83ac02ec730 19 (unreleased) cited
Don't include access/htup_details.h in executor/tuptable.h
- 1a8b5b11e48a 19 (unreleased) cited
Refactor to avoid code duplication in transformPLAssignStmt.
- b0fb2c6aa5a4 19 (unreleased) cited
Avoid including commands/dbcommands.h in so many places
- 325fc0ab14d1 19 (unreleased) cited
Restrict psql meta-commands in plain-text dumps.
- 71ea0d679543 19 (unreleased) cited
Split func.sgml into more manageable pieces
- 4e23c9ef65ac 19 (unreleased) cited
Fix squashing algorithm for query texts
- 0f65f3eec478 18.0 cited
EXPLAIN: Always use two fractional digits for row counts.
- 95dbd827f2ed 18.0 cited
Preliminary refactoring of plpgsql expression construction.
- a654af21ae52 18.0 cited
plpgsql: pure parser and reentrant scanner
- 7b27f5fd36cb 18.0 cited
Add some sanity checks in executor for query ID reporting
- 24f520594809 18.0 cited
Fix misleading error message context
- 4af123ad45bd 18.0 cited
Add macros for looping through a List without a ListCell.
- 14dd0f27d7cd 17.0 cited

Attachments

schema-variables-poc-180321-01-diff (application/octet-stream)

2018-03-20 18:38 GMT+01:00 Pavel Stehule <pavel.stehule@gmail.com>:

> Hi
>
> I am sending new update. The code is less ugly, and the current
> functionality is +/- final for first stage. It should be good enough for
> playing and testing this concept.
>
> What is supported:
>
> 1. scalar, composite and array variables
> 2. composite can be defined on place or some composite type can be used
> 3. variable, or any field of variable, can have defined default value
> 4. variable is database object - the access rights are required
> 5. the values are stored in binary form with defined typmod
>
> An usage is very simple:
>
> postgres=# create variable foo as numeric default 0;
> CREATE VARIABLE
> postgres=# select foo;
> ┌─────┐
> │ foo │
> ╞═════╡
> │   0 │
> └─────┘
> (1 row)
>
> postgres=# let foo = pi();
> LET
> postgres=# select foo;
> ┌──────────────────┐
> │       foo        │
> ╞══════════════════╡
> │ 3.14159265358979 │
> └──────────────────┘
> (1 row)
>
> postgres=# create variable boo as (x numeric default 0, y numeric default
> 0);
> CREATE VARIABLE
> postgres=# let boo.x = 100;
> LET
> postgres=# select boo;
> ┌─────────┐
> │   boo   │
> ╞═════════╡
> │ (100,0) │
> └─────────┘
> (1 row)
>
> postgres=# select boo.x;
> ┌─────┐
> │  x  │
> ╞═════╡
> │ 100 │
> └─────┘
> (1 row)
>
> Please try it.
>

small fix - support for SQL functions


>
> Regards
>
> Pavel
>