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Re:Left to Right Programming by taeric on Monday August 18, 2025 @05:17PM (#44945440)
My main caveat here, is that often the person starting a select knows what they want to select before they know where to select it from. To that end, having autocomplete for the sources of columns is far far more useful than autocomplete for columns from a source.

I will also hazard a guess that the total number of columns most people would need autocomplete for are rather limited? Such that you can almost certainly just tab complete for all columns, if that is what you really want/need. The few of us that are working with large databases probably have a set of views that should encompass most of what we would reasonably be able to get from the database in a query.

Re:Left to Right Programming by jayd16 on Monday August 18, 2025 @06:18PM (#44945889)
Seems nonsensical. Column names have no meaning without the table. Table is the object, columns are the properties. What language goes Property.Object? All popular languages have this wrong?
Re:Left to Right Programming by taeric on Monday August 18, 2025 @06:45PM (#44946106)
I'm assuming you are largely just not thinking this one through? We are not modeling the domain, we are describing some data we want to select. Without knowing how it is modeled, I can give a brief "top line" for expected select statements on many data models. "I want average_weather, year, zip_code", "I want year, college_name, degree_name, median_graduate_salary, mean_graduate_salary", "..."

I don't think it is tough to describe many many reports of data that you would want in this way. Is it enough for you to flat out get the answer? No, of course not. But nor is it enough to just start all queries at what possible tables you could use as a starting point.

Re:Left to Right Programming by debazel on Monday August 18, 2025 @07:05PM (#44946256)
How would you even know it's possible get the data before you've chosen a table?

Your example is also not a complete select statement, you would need to go back and add the actual aggregate functions, and oops the zip_code column was actually called zip, so we need to remap that as well. You can almost never finish a select statement before you have inspected the tables, so why not just start there immediately?

Re:Left to Right Programming by taeric on Monday August 18, 2025 @07:12PM (#44946319)
Often times you don't know it is possible to get some data without consulting the table? Worse, you probably need to consult the views that have been made by any supporting DB team before you go off and build your own rollups. Unless you like not taking advantage of any aggregate jobs that are running nightly for reporting.

And to be clear, I'm all for complaining about the order of a select statement, to a very large degree. It is done in such a way that you have to jump back and forth as you are constructing the full query. That can feel a bit painful.

However, I don't know that it is just the SELECT before FROM that causes this jumping back and forth and fully expect that you would jump around a fair bit even with the FROM first. More, if I am ever reworking a query that the system is running, I treat the SELECT as the contract to the application, not the FROM.

There is a bit of "you should know the database before you can expect to send off a good query", but that really cuts to any side of this debate? How do you know the tables you want so well, but you don't know the columns you are going to ask for?

Re:Left to Right Programming by debazel on Monday August 18, 2025 @07:33PM (#44946496)
> How do you know the tables you want so well, but you don't know the columns you are going to ask for?

Simply because there are a lot more columns than there are tables.

Of course, I sometimes forget the exact table name as well. However, this is mostly not an issue as the IDE knows all table names before anything has been entered. By simply entering `FROM user`, the autocomplete will list all tables that contain `user`, and I can complete it from there. I cannot do the same with the column selection unless I first write the FROM part. And even if I do know exactly which columns and tables I want I would still want autocomplete to work when creating the SELECT statement. Rather than typing `zip_code`, I can most likely just type `z<TAB>`.

That is why 99% of my select queries start as `SELECT * FROM mytable`, and then I go back to fill in the select statement. And it's not just me, all colleagues I've worked with does exact same thing.

For larger, more complicated queries, you'll have to go back and forth a lot as you join tables together, that is unavoidable, but 80-90% of my queries could be finished in one go if the FROM part came first.

Re:Left to Right Programming by taeric on Monday August 18, 2025 @08:35PM (#44946995)
But "more columns than there are tables" is also why I put the thing about, "the total number of columns most people would need autocomplete for are rather limited?" I could see an argument on how this mattered back at the origin of SQL, but today? It is entirely conceivable that you can autocomplete the column names with it updating the from as necessary for the columns you have selected. You could then tab to the from and pick alternative tables with natural joins prefilled between the tables. With very minimum effort.

I actually seem to recall this was done in some of the early dedicated SQL tools. It is rather amusing how much we handicap ourselves by not using some things older tools built.

Re:Left to Right Programming by jimbokun on Monday August 18, 2025 @11:22PM (#44947946)
How did you know it was zip_code and not ZipCode?

Maybe in this case you know the same naming conventions are enforced across all tables. But in general it’s difficult to know the exact column name without looking it up first.

Re:Left to Right Programming by lelanthran on Tuesday August 19, 2025 @01:38AM (#44948566)
> How did you know it was zip_code and not ZipCode?

I think you're missing the point; you start off with your goal, regardless of the column name. No one has the goal "we want columsn from this specific table", it's always "we want these columns in the final output".

Re:Left to Right Programming by prollings on Tuesday August 19, 2025 @07:32AM (#44950421)
Right, but which columns? The goal absolutely IS to select columns from a table. ie. my goal is not to select created_at, my goal is to select Foo's created_at.
Re:Left to Right Programming by lelanthran on Tuesday August 19, 2025 @08:13AM (#44950694)
> The goal absolutely IS to select columns from a table.

No. The goal is to have an output column $FOO, where $FOO is meaningful and might not even be in the database in the first place.

> my goal is not to select created_at, my goal is to select Foo's created_at.

Then your goal is to get a value out of a specific table, namely `Foo`, presumably because the end-user wants to see some value in the results.

The end-user getting the value has neither an interest in nor knowledge of your schema. `Foo.created_at` is no more meaningful in the result sets than an unadorned `created_at`.

For this specific example, the end-user might want a column in the output called `age` (if it came from an inventory table`, or `duration` (if it came from a metrics tables), or perhaps `expiry` (if it is a table containing perishable stock). These are all a column in a Foo table, but the request that caused you to write the query in the first place does not mention table at all.

You get their requirement as either `age`, `duration`, `expiry` or similar. That is what you are starting from: "a need for a specific piece of data". You are not starting from "a need from a specific table", because the information needed is coming from someone who neither knows nor cares what your schema looks like.

Re:Left to Right Programming by kragen on Monday August 18, 2025 @09:14PM (#44947218)
Anytime you store a single property for all objects in an array or hash table, so, Fortran, BASIC, APL, Numpy, R, awk, and sometimes Perl. Parallel arrays are out of style but certainly not unheard of. They're the hot new thing in games programming, under the name "entity-component-system".

Even C when `property` is computed rather than materialized. And CLOS even uses that syntax for method invocation.

The only language I can think of that uses field(record) syntax for record field access is AT&T-syntax assembly.

Re:Left to Right Programming by ajuc on Tuesday August 19, 2025 @03:11AM (#44949036)
When languages use order property, object - it's usually because they treat the properties as functions.

name(object) makes as much sense as object.name

Re:Left to Right Programming by Zedseayou on Monday August 18, 2025 @05:36PM (#44945598)
Can you help me understand this situation? Almost always what I want to select is downstream of what I am selecting from, I can't write anything in SELECT until i understand the structure/columns available in FROM.
Re:Left to Right Programming by taeric on Monday August 18, 2025 @05:47PM (#44945691)
"I want 'first_name, last_name, and average(grade)' for my report." That is easy enough to state without knowing anything about how the data is normalized.

Back when I worked to support a data science team, I actually remember taking some of their queries and stripping everything but the select so that I could see what they were trying to do and I could add in the correct parts of the rest.

Re:Left to Right Programming by mamcx on Monday August 18, 2025 @06:15PM (#44945874)
Even assuming that this is plausible way a user could think about it (that can be understood) it shows why is bad

Think: I have 20 tables with the column `id`

"I want 'id,id,id'"

is bad UX, and is what here is being argued, then when the syntax guide you: "I want 'FROM a: id'" is better

Re:Left to Right Programming by taeric on Monday August 18, 2025 @06:31PM (#44945981)
I don't think anyone would ever say they want "id, id, id"? They would say they want "customer_id, order_id, item_id" or some such. You would then probably say, "we just use 'id' for the id of every item..." but many places that I've worked actually explicitly didn't do that for essentially this reason. Natural joins on "foo_id" "just work" if you don't give every table the same "id" column.
Re:Left to Right Programming by mamcx on Tuesday August 19, 2025 @02:25PM (#44954639)
That is what the syntax allow. And is the user that need to "patch" the meaning using other things like alias, renames or hopefully, proper names for fields (by the way "id, id, id" happens a lot in the wild!)

Is like "to control mutation I only need to append "mut" to the name!

Re:Left to Right Programming by necovek on Monday August 18, 2025 @11:48PM (#44948080)
Current SELECT syntax does allow one to "SELECT user.id as user_id, product.id as product_id..." which can then even autocomplete the FROM for you from your query "declaration" (a-la function declaration, in particular its return type).
Re:Left to Right Programming by jayd16 on Monday August 18, 2025 @06:24PM (#44945928)
This assumes I have all the column memorized but not all the tables?

Even in your example, first and last could refer to student or teacher. But presumably you know you're looking for student data before knowing the exact columns.

Re:Left to Right Programming by taeric on Monday August 18, 2025 @06:40PM (#44946071)
No, this assumes you know what you want for a query. Which, seems largely fair?

Like, how would you send this question to someone? Or how would you expect it to be sent to you? If your boss doesn't tell you from what table they want some data, do you just not answer?

And sure, there could be ambiguities here. But these are not really fixed by listing the sources first? You would almost certainly need to augment the select to give the columns names that disambiguate for their uses. For example, when you want the teacher and the student names, both.

And this is ignoring more complications you get from normalized data that is just flat out hard to deal with. I want a teacher/student combination, but only for this specific class and term, as an example. Whether you start the from at the student, the class, or the term rosters feels somewhat immaterial to how you want to pull all of that data together for why ever you are querying it.

Re:Left to Right Programming by jayd16 on Monday August 18, 2025 @07:33PM (#44946500)
If my boss asks me for a zip code, I'm going to ask "for what?"

If they ask for "address for a customer" I can go to the customer table and look up what FKs are relevant and collect all possible data and then narrow down from there.

Re:Left to Right Programming by taeric on Monday August 18, 2025 @08:29PM (#44946945)
I'd assume they would ask for "aggregate sales by month to zip codes," or some such. Which, you'd probably get from a reporting table, and not bother trying to do the manual aggregate over transactional data. (That is, OLAP versus OLTP is a very real divide that you can't wave away.)

Realistically, I strongly suspect you could take this argument either direction. If you have someone making a query where they are having to ask "what all tables could I start from?" you are in for some pain. Often the same data is reachable from many tables, and you almost certainly have reasons for taking certain paths to get to it. Similarly, if they should want "person_name", heaven help them.

Such that, can you contrive scenarios where it makes sense to start the query from the from clause? Sure. My point is more that you almost certainly have the entire query conceptualized in your mind as you start. You might not remember all of the details on how some things are named, but the overall picture is there. Question then comes down to if one way is more efficient than the other? I have some caveats that this is really a thing hindered by the order of the query. We don't have data, of course, and are arguing based on some ideas that we have brought with us.

So, would I be upset if the order was reversed? Not at all. I just don't expect that would actually help much. My memory is using query builders in the past where I would search for "all tables that have customer_id and order_id in them" and then, "which table has customer_id and customer_address" and then... It was rarely (ever?) the name of the table that helped me know which one to use. Rather, I needed the ones with the columns I was interested in.

Re:Left to Right Programming by shkkmo on Monday August 18, 2025 @10:58PM (#44947833)
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.

Re:Left to Right Programming by necovek on Monday August 18, 2025 @11:55PM (#44948113)
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).

Re:Left to Right Programming by shkkmo on Tuesday August 19, 2025 @02:21PM (#44954591)
> 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.

Re:Left to Right Programming by Izkata on Tuesday August 19, 2025 @05:07PM (#44956270)
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.
Re:Left to Right Programming by Izkata on Monday August 18, 2025 @08:43PM (#44947048)
Likewise when skimming code, having the attributes on the left and details on the right makes it much easier to see the data flow in the larger program - it's the same order as "var foo = bar()".
Re:Left to Right Programming by jimbokun on Monday August 18, 2025 @11:19PM (#44947936)
I can’t think of an example where I knew the columns I wanted to select before I knew which table I wanted to select them from.
Re:Left to Right Programming by necovek on Monday August 18, 2025 @11:42PM (#44948056)
Did you ever not do things like

  select name, min(price) from product join product_price on product.id = product_price.product_id
where you start with "I need a product name and minimum price" before thinking about where they come from?

The more one uses SQL to filter for, the more you'll think about what you want to achieve vs how (which comes after): in a sense, the SELECT is your function return type declaration, and I frequently start my functions with the declaration.

Re:Left to Right Programming by masklinn on Tuesday August 19, 2025 @02:59AM (#44948968)
> where you start with "I need a product name and minimum price" before thinking about where they come from?

Sure, and pretty much every time the names I wrote up were not the ones in the table so that was a complete waste of time.

> the SELECT is your function return type declaration

That might be true if “select” only contained aliases, bur that’s not the case at all, so what it is is complete nonsense.

Re:Left to Right Programming by taeric on Tuesday August 19, 2025 @11:51AM (#44952976)
This presumes that you never pick the wrong table, as well? :D

My argument would be largely that you are doing a search of all of the tables for the columns that you want. With having to know the way to join the necessary tables along the way.

And I want to be clear, I don't think this is necessarily "the way." I more think that it is almost certainly an iterative process that can be started at either place, and will require bouncing between the two quite often.

For instance, yes, you can autocomplete column names from tables that you have put in the from. What if you can't find the column you are anticipating there? Go back and rescan the table names hoping you can guess which table should have the column you want? Then go back to autocomplete for columns to see if expected value appears? Or go to a bit more of a global search for columns?

Either way should be fine.

Re:Left to Right Programming by jimbokun on Tuesday August 19, 2025 @01:04PM (#44953737)
Nope.