Re: What type of Compiler to SQL? Memory-Image (Load-and-Go) Format?

On Fri, May  5, 2023 at 01:00:37AM +0000, Wen Yi wrote:
> Hi team,
> I am a newbie to the postgres.
> When I am studying the compiler,the text book tell me there is there type of
> compiler.
> 
>  1. Assembly Language Format
>  2. Relocatable Binary Format
>  3. Memory-Image (Load-and-Go) Format
> 
> I check the postgres's sql compiler, and it's achieved by lex & yacc.
> So What type of Compiler to SQL? Is Memory-Image (Load-and-Go) Format ?

Lex and yacc load command-specific structures, or a Query structure for
SELECT, INSERT, UPDATE, DELETE, MERGE.

The Query structure is converted into a Plan which is executed by the
executor.  It is not compiled into assembly language.  See this:

    https://www.postgresql.org/developer/backend/

A
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