Possible additional sql-ops
Marijn Haverbeke
marijnh at gmail.com
Sat Oct 26 20:11:26 UTC 2013
These look sane. I'd unify :partition-by and :partition-by-order-by
into a single operation (:partition-by ... :order-by ...) by using
split-on-keywords. If you could submit a pull request, preferably even
with some documentation, I'll be happy to merge it in.
Best,
Marijn
On Sat, Oct 26, 2013 at 6:22 PM, Sabra Crolleton
<sabra.crolleton at gmail.com> wrote:
> I have been writing queries requiring window functions and recursive with
> functions. I finally decided to try to write some sql-ops so that I can use
> s-sql. They work for me but would appreciate comments. I did include a
> :parens op because I find that sometimes I just need an additional set of
> parens for an sql query. Below are the functions, the amendments to :select
> and :order-by and usage examples.
>
> (def-sql-op :over (form &rest args)
> (if args `("(" ,@(sql-expand form) " OVER " ,@(sql-expand-list args) ")")
> `("(" ,@(sql-expand form) " OVER ()) ")))
>
> (def-sql-op :partition-by (&rest args)
>
> `("(PARTITION BY " ,@(sql-expand-list args) ")"))
>
> (def-sql-op :partition-by-order-by (form &rest fields)
> `("(PARTITION BY " ,@(sql-expand form) " ORDER BY " ,@(sql-expand-list
> fields) ") "))
>
> (def-sql-op :parens (op) `(" (" ,@(sql-expand op) ") "))
>
> (def-sql-op :with (&rest args)
> (let ((x (butlast args)) (y (last args)))
> `("WITH " ,@(sql-expand-list x) ,@(sql-expand (car y)))))
>
> (def-sql-op :with-recursive1 (form1 form2)
> `("WITH RECURSIVE " ,@(sql-expand form1) ,@(sql-expand form2)))
>
> (def-sql-op :window (form)
> `("WINDOW " ,@(sql-expand form)))
>
>
> Amendment to :select (to pick up the new "window" arg
>
> (def-sql-op :select (&rest args)
> (split-on-keywords ((vars *) (distinct - ?) (distinct-on * ?) (from * ?)
> (window ?) (where ?) (group-by * ?)
> (having ?)) (cons :vars args)
> `("(SELECT "
> ,@(if distinct '("DISTINCT "))
> ,@(if distinct-on `("DISTINCT ON (" ,@(sql-expand-list distinct-on) ")
> "))
> ,@(sql-expand-list vars)
> ,@(if from (cons " FROM " (expand-joins from)))
> ,@(if window (cons " WINDOW " (sql-expand-list window)))
> ,@(if where (cons " WHERE " (sql-expand (car where))))
> ,@(if group-by (cons " GROUP BY " (sql-expand-list group-by)))
> ,@(if having (cons " HAVING " (sql-expand (car having))))
> ")")))
>
> Amendment to :order-by to pick up the situation where the only arg is the
> form
>
>
> (def-sql-op :order-by (form &rest fields)
> (if fields
> `("(" ,@(sql-expand form) " ORDER BY " ,@(sql-expand-list fields) ")")
> `("( ORDER BY " ,@(sql-expand form) ")")))
>
>
> Usage Examples:
> Over Examples generally following
> http://www.postgresql.org/docs/9.3/static/tutorial-window.html
>
> (query (:select 'salary (:over (:sum 'salary))
> :from 'empsalary))
>
> (query (:select 'depname 'empno 'salary
> (:over (:avg 'salary)
> (:partition-by 'depname))
> :from 'empsalary))
>
>
> (query (:select 'depname 'empno 'salary
> (:over (:rank)
> (:partition-by-order-by 'depname (:desc 'salary)))
> :from 'empsalary))
>
> (query (:select (:over (:sum 'salary) 'w)
> (:over (:avg 'salary) 'w)
> :from 'empsalary :window
> (:as 'w (:partition-by-order-by 'depname
> (:desc 'salary)))))
>
>
> With Examples
>
> (query (:with (:as 'upd
>
> (:parens
> (:update 'employees :set 'sales-count (:+ 'sales-count 1)
> :where (:= 'id
> (:select 'sales-person
> :from 'accounts
> :where (:= 'name "Acme
> Corporation")))
> :returning '*)))
> (:insert-into 'employees-log
> (:select '* 'current-timestamp :from
> 'upd))))
>
> With-Recursive Examples following
> http://www.postgresql.org/docs/current/static/queries-with.html
>
> (query (:with-recursive
> (:as (:t1 'n)
> (:union-all (:values 1)
> (:select (:+ 'n 1)
> :from 't1
> :where (:< 'n 100))))
> (:select (:sum 'n) :from 't1)))
>
> (query (:with-recursive
> (:as (:included_parts 'sub-part 'part 'quantity)
> (:union-all
> (:select 'sub-part 'part 'quantity
> :from 'parts
> :where (:= 'part "our-product"))
> (:select 'p.sub-part 'p.part 'p.quantity
> :from (:as 'included-parts 'pr)
> (:as 'parts 'p)
> :where (:= 'p.part 'pr.sub-part) )))
> (:select 'sub-part (:as (:sum 'quantity) 'total-quantity)
> :from 'included-parts
> :group-by 'sub-part)))
>
> (query (:with-recursive
> (:as (:search-graph 'id 'link 'data 'depth)
> (:union-all (:select 'g.id 'g.link 'g.data 1
> :from (:as 'graph 'g))
> (:select 'g.id 'g.link 'g.data (:+ 'sg.depth 1)
> :from (:as 'graph 'g) (:as 'search-graph
> 'sg)
> :where (:= 'g.id 'sg.link))))
> (:select '* :from 'search-graph)))
>
> (query (:with-recursive
> (:as (:search-graph 'id 'link 'data'depth 'path 'cycle)
> (:union-all
> (:select 'g.id 'g.link 'g.data 1
> (:[] 'g.f1 'g.f2) nil
> :from (:as 'graph 'g))
> (:select 'g.id 'g.link 'g.data (:+ 'sg.depth 1)
> (:|| 'path (:row 'g.f1 'g.f2))
> (:= (:row 'g.f1 'g.f2)
> (:any* 'path))
> :from (:as 'graph 'g)
> (:as 'search-graph 'sg)
> :where (:and (:= 'g.id 'sg.link)
> (:not 'cycle)))))
> (:select '* :from 'search-graph)))
>
>
>
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