Re: PostgreSQL Function Language Performance: C vs PL/PGSQL

Ah, that clears things up. Yes, the connections are more or less persistent. I have a connection manager which doles connections out to the worker threads and reclaims them when the workers are done with them. It dynamically adds new connections based on load. Each worker obtains a connection from the connection manager, performs a transaction which involves executing the function and pulling back the results from the cursors, then releases the connection back to the connection manager for other workers to use. So, this means that even when written in C, the SQL queries will be planned and cached on each connection after the first execution. So, I guess the question just becomes whether using SPI in C has any extra overhead verses using PL/PGSQL which might make it slower for performing queries. Since PostgreSQL is written in C, I assume there is no such additional overhead. I assume that the PL/PGSQL implementation at its heart also uses SPI to perform those executions. Is that a fair statement?




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