Saturday, September 29, 2018

SQL Joins (In Postgres)

Our beloved Structured Query Language may be the lingua franca for relational databases-but like many languages, SQL is in a state of constant evolution. The first releases of SQL didn't even have a notation for joins. At the time, SQL only supported inner joins.

Cross Joins and Where Filters

As a result, back in the early eighties, the only way to express a join condition between tables would be in the WHERE clause.



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