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0 pointsshkkmo7mo ago0 comments

Your approach only works with massive assumptions about the structure of the data or a very simplistic data structure.

SELECT statments don't just use table names, they can use aliases for those table names, views, subqueries, etc.

The FROM / JOIN blocks are where the structure of the data your are selecting from is defined. You should not assume you understand what a SELECT statement means until you have read those blocks.

0 comments

necovek7mo ago

As GP said, you can take this both ways.

I can define the return format of my query in the SELECT statement, then adapt the data structure in the FROM block using subselects, aliases etc — all to give me the shape desired for the query.

If you've ever done complex querying with SQL, you'd know that you'd go back and forth on all parts of the query to get it right unless you knew the relations by heart, regardless of the order (sometimes you'll have to rework the FROM because you changed the SELECT is the point).

shkkmoOP7mo ago

> As GP said, you can take this both ways.

You can, but one of those ways is objectively worse for the reasons explained in this thread and in the article.

When you have to read a query out of order to understand it then something is wrong with the structure of the query language.

Izkata7mo ago

And the objectively worst way is to put the SELECT in the middle, because it ignores the relationship between the query and the rest of the code that interacts with it, making it more difficult to read - and reading the code is done a lot more than writing the code.

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