4

I have a question, about the internal handling of array columns in Postgres. Does the engine handle it as a classical array with memory alloc or is it somehow a pointer list.

It would be interesting to know - I have a few questions to answer myself concerning performance... :)

  • 3
    Why not take a look at the source code? Or, possibly, you could ask this on a postgresql list as well. – dezso Nov 9 '12 at 16:48
6

Arrays are defined in src/includes/utils/array.h and src/backend/utils/adt/arrayfuncs.c and the other array* files in src/backend/utils/adt/.

An array is a VARLENA (see src/backend/utils/adt/varlena.c) which is a palloc()'d type, a scoped-storage wrapper around malloc(). Arrays are block-allocated data, not linked lists.

  • 1
    Good to have PostgreSQL expertise from specialists with a source code level understanding of RDBMS on DBA.SE, right? :) – dezso Nov 10 '12 at 8:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.