CTE = common table expression, i.e. a WITH clause (possibly recursive) before yo...

stormdennis · on Feb 1, 2023

Yes, I didn't know what it was so I had looked it up before I saw yours. The definition I got is below:

A common table expression, or CTE, is a temporary named result set created from a simple SQL statement that can be used in subsequent SELECT, DELETE, INSERT, or UPDATE statements.

xpil · on Feb 1, 2023

> (...) in subsequent SELECT, DELETE, INSERT, or UPDATE statements

The annoying part is that certain RDMBS engines (MySQL for instance) require you to write the INSERT keyword before any CTEs.

So, your T-SQL or PGSQL query:

`with cte1 as (...) insert into ... select ... from cte1;`

becomes:

`insert into ... with cte1 as (...) select ... from cte1;`

I know the difference is minor but when you deal with many different DB engines, it is simply annoying.

gpvos · on Feb 1, 2023

I knew about WITH clauses, just didn't know the name.