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IMO better would be a database interface that acts as a normal programming language, treating tables as arrays of records. Compare: how many teachers older

IMO better would be a database interface that acts as a normal programming language, treating tables as arrays of records. Compare: how many teachers older than 30 teachers.filter(*.age > 30).len Same length, but the second one has a degree of precision that the first lacks. (Though they might diverge somewhat as the complexity of queries grows, I suspect programming languages would do better as they have better facilities for symbolic manipulation.) Note also that the second example (and your SQL example) had to specify the table's name, while the natural language one did not—another mark against the natural language solution.

Luuseens 6y ago
What you described sounds a lot like .NET's LINQ, which translates to SQL queries as well: teachers.Where(t => t.Age > 30).Count();
- moonchild 6y ago
  Linq is cool; I haven't really had opportunity to play with it as I'm not in the .net ecosystem. Another integrated language/database is kdb, although it borrows somewhat from sql's syntax.
mstade 6y ago
Your example reminds me of RethinkDB, which I haven't used in years but as I recall it was quite nice!
erezsh 6y ago
I would suggest something more like: teachers[age > 30].count (Because I'm working on something exactly like this right now)
- moonchild 6y ago
  In apl (incl. apl-alikes—kdb, etc.), you can essentially say this directly. 'age > 30' produces an array with the same shape as 'age' with a 1 for instances that are >30 and 0 else. So for instance: 27 42 44 > 30 0 1 1 If all you want is a count of teachers older than 30, you can simply sum up the resulting array, so: +/0 1 1 ⍝note: '/' is reduction, so +/ is sum reduction 2 If you want the indices, you can use 'where', which will produce an array of indices corresponding to 1s in its argument, so ⍸0 1 1 1 2 Indicates that '0 1 1' has 1s at indices 1 and 2. (We could also take the length of this array to get the count of teachers older than 30, although that would be a bit silly compared to just summing the original array.) We can then use these indices to index a different array: ages←27 42 44 names←'anthony' 'barbara' 'bert' names[1 2] barbara bert names[⍸ ages>30] barbara bert However, we don't even need to use 'where' in this case; the reduction operator (/) has a second use which lets us say: 0 1 1 / names barbara bert (ages > 30) / names barbara bert Good luck with your database, and hope this helps!
slifin 6y ago
It's possible to use Clojure/ClojureScript functions inside datalog queries http://www.learndatalogtoday.org/ http://www.learndatalogtoday.org/

Luuseens 6y ago

What you described sounds a lot like .NET's LINQ, which translates to SQL queries as well: teachers.Where(t => t.Age > 30).Count();

moonchild 6y ago
Linq is cool; I haven't really had opportunity to play with it as I'm not in the .net ecosystem. Another integrated language/database is kdb, although it borrows somewhat from sql's syntax.

mstade 6y ago

Your example reminds me of RethinkDB, which I haven't used in years but as I recall it was quite nice!

erezsh 6y ago

I would suggest something more like: teachers[age > 30].count (Because I'm working on something exactly like this right now)

moonchild 6y ago
In apl (incl. apl-alikes—kdb, etc.), you can essentially say this directly. 'age > 30' produces an array with the same shape as 'age' with a 1 for instances that are >30 and 0 else. So for instance: 27 42 44 > 30 0 1 1 If all you want is a count of teachers older than 30, you can simply sum up the resulting array, so: +/0 1 1 ⍝note: '/' is reduction, so +/ is sum reduction 2 If you want the indices, you can use 'where', which will produce an array of indices corresponding to 1s in its argument, so ⍸0 1 1 1 2 Indicates that '0 1 1' has 1s at indices 1 and 2. (We could also take the length of this array to get the count of teachers older than 30, although that would be a bit silly compared to just summing the original array.) We can then use these indices to index a different array: ages←27 42 44 names←'anthony' 'barbara' 'bert' names[1 2] barbara bert names[⍸ ages>30] barbara bert However, we don't even need to use 'where' in this case; the reduction operator (/) has a second use which lets us say: 0 1 1 / names barbara bert (ages > 30) / names barbara bert Good luck with your database, and hope this helps!

slifin 6y ago

It's possible to use Clojure/ClojureScript functions inside datalog queries http://www.learndatalogtoday.org/ http://www.learndatalogtoday.org/