PostgreSQL索引顾问

<p> <a href=""><img src="https://yellow-cdn.veclightyear.com/2b54e442/a62310cf-4f62-416f-807a-dabb154de42e.svg" alt="PostgreSQL版本" height="18"></a> <a href="https://github.com/supabase/index_advisor/blob/master/LICENSE"><img src="https://img.shields.io/github/license/supabase/index_advisor" alt="许可证" height="18"></a> <a href="https://github.com/supabase/index_advisor/actions"><img src="https://yellow-cdn.veclightyear.com/2b54e442/0ba5628a-bf96-4b1e-82c4-3aece54361d3.svg" alt="测试" height="18"></a> </p>

一个用于推荐索引以提高查询性能的PostgreSQL扩展。

功能

• 支持通用参数，如$1、$2
• 支持物化视图
• 识别被视图混淆的表/列

API

描述

对于给定的查询，搜索一组可以改善查询执行时间的SQL DDL create index语句；

签名

index_advisor(query text)
returns
    table  (
        startup_cost_before jsonb,
        startup_cost_after jsonb,
        total_cost_before jsonb,
        total_cost_after jsonb,
        index_statements text[],
        errors text[]
    )

使用方法

对于最简单的示例，可以给index_advisor函数一个单表查询，其中包含对未索引列的过滤。

create extension if not exists index_advisor cascade;

create table book(
  id int primary key,
  title text not null
);

select
    *
from
  index_advisor('select book.id from book where title = $1');

 startup_cost_before | startup_cost_after | total_cost_before | total_cost_after |                  index_statements                   | errors
---------------------+--------------------+-------------------+------------------+-----------------------------------------------------+--------
 0.00                | 1.17               | 25.88             | 6.40             | {"CREATE INDEX ON public.book USING btree (title)"} | {}

(1 row)

更复杂的查询可能会生成额外的建议索引

create extension if not exists index_advisor cascade;

create table author(
    id serial primary key,
    name text not null
);

create table publisher(
    id serial primary key,
    name text not null,
    corporate_address text
);

create table book(
    id serial primary key,
    author_id int not null references author(id),
    publisher_id int not null references publisher(id),
    title text
);

create table review(
    id serial primary key,
    book_id int references book(id),
    body text not null
);

select
    *
from
    index_advisor('
        select
            book.id,
            book.title,
            publisher.name as publisher_name,
            author.name as author_name,
            review.body review_body
        from
            book
            join publisher
                on book.publisher_id = publisher.id
            join author
                on book.author_id = author.id
            join review
                on book.id = review.book_id
        where
            author.id = $1
            and publisher.id = $2
    ');

 startup_cost_before | startup_cost_after | total_cost_before | total_cost_after |                  index_statements                         | errors
---------------------+--------------------+-------------------+------------------+-----------------------------------------------------------+--------
 27.26               | 12.77              | 68.48             | 42.37            | {"CREATE INDEX ON public.book USING btree (author_id)",   | {}
                                                                                    "CREATE INDEX ON public.book USING btree (publisher_id)",
                                                                                    "CREATE INDEX ON public.review USING btree (book_id)"}
(3 rows)

安装

需要安装了hypopg的Postgres。

git clone https://github.com/supabase/index_advisor.git
cd index_advisor
sudo make install

运行测试

make install; make installcheck