topic Re: hash vs proc sql join in SAS Programming

hash vs proc sql join

Babloo — Thu, 31 Jan 2019 06:10:26 GMT

Could you please help me understand the difference between hash join and proc sql join?

Re: hash vs proc sql join

Kurt_Bremser — Thu, 31 Jan 2019 06:19:36 GMT

Maxim 1: Read the Documentation

Data Step Component Objects

SQL Procedure Users Guide

Re: hash vs proc sql join

Kurt_Bremser — Thu, 31 Jan 2019 06:51:12 GMT

And use the search function of the communities to find hash- and SQL-related posts.

Re: hash vs proc sql join

novinosrin — Thu, 31 Jan 2019 06:23:31 GMT

Hi @Babloo , Besides documentation, why not invest in some books offered by SAS press?

PROC SQL: Beyond the Basics Using SAS, Second Edition

Re: hash vs proc sql join

LinusH — Thu, 31 Jan 2019 08:33:40 GMT

Perhaps just adding confusion, but "hash" is a quite generic term. If one refer to the programming technique in the data step, I think we should call it Hash Table (join).

Because, you can do hash joins in SQL as well (but here it happens behind the scenes given certain criteria’s, upon which the optimizer makes a decision what algorithm to use).

Re: hash vs proc sql join

Kurt_Bremser — Thu, 31 Jan 2019 10:14:20 GMT

And that's a very fine introduction to hash programming:

SAS Hash Object Programming Made Easy