How PostgreSQL parses the query and constructs the Parse Tree?

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In the previous video, we delved into the client connection process in the PostgreSQL database. In this video, we explored the source code to comprehend how PostgreSQL handles SQL queries from clients and processes them into a parse tree. The lexer file defines tokens like space, database, etc., while the grammar file establishes rules for query execution. The abstract syntax tree is generated to execute queries. Open Source tools like Flex and Bison are used to generate C code for lexer and grammar files. The build process compiles these files into the PostgreSQL binary for server management.

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[k.k.gayansanjeewa]

this encourage me, more dig in to these stuff too . Since it just open up the stuff and make the decision making stages very clear .

[onkar_rajopadhye]

@AsliEngineering: Very informative which serves as a nice refresher to lexer, parser, parse tree as well as flex, bison. Thanks for that!
Couple of suggestions:
1. In a future video on this, cover parse tree in more depth.
2. Cover PG's rewrite engine and optimizer.
Thanks again!

[dharins]

Very Detailed video, thanks for diving in

[mayank]

Super informative. This got me curious about these interesting stuff again, Thanks Arpit!

[kritibindra]

This is awesome! I really love how you tell how you were able to find things like scan.l being converted to scan.c etc. It helps us in understanding how to go through the code files. Arpit, can you cover query execution plan of DBs and how can they affect performance? Or have you already covered in previous videos?

[sparsh]

This video was super informative, Arpit!!!

[physicsakhada]

Deadlocks and transaction please in depth😊

[SaketAnandPage]

How did you make this Red Color Pen with sparkles in Good Notes?

[architectingme]

Arpit, which device and software are you using to teach? It would be helpful if you share the info

[rishabhthakur]

I always find the compiler design the worst topic but the way you explain the things made me fall in love with the subject or topic.