home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Dream 44
/
Amiga_Dream_44.iso
/
RiscPc
/
programmation
/
scm4e2.arc
/
!Scm
/
slib
/
rdms
< prev
next >
Wrap
Text File
|
1994-12-17
|
20KB
|
600 lines
;;; "rdms.scm" rewrite 6 - the saga continues
; Copyright 1994 Aubrey Jaffer
;
;Permission to copy this software, to redistribute it, and to use it
;for any purpose is granted, subject to the following restrictions and
;understandings.
;
;1. Any copy made of this software must include this copyright notice
;in full.
;
;2. I have made no warrantee or representation that the operation of
;this software will be error-free, and I am under no obligation to
;provide any services, by way of maintenance, update, or otherwise.
;
;3. In conjunction with products arising from the use of this
;material, there shall be no use of my name in any advertising,
;promotional, or sales literature without prior written consent in
;each case.
(define rdms:catalog-name '*catalog-data*)
(define rdms:domains-name '*domains-data*)
(define rdms:columns-name '*columns*)
(define catalog:init-cols
'((1 #t table-name #f atom)
(2 #f column-limit #f uint)
(3 #f coltab-name #f atom)
(4 #f bastab-id #f base-id)
(5 #f user-integrity-rule #f expression)
(6 #f view-procedure #f expression)))
(define catalog:column-limit-pos 2)
(define catalog:coltab-name-pos 3)
(define catalog:bastab-id-pos 4)
(define catalog:integrity-rule-pos 5)
(define catalog:view-proc-pos 6)
(define columns:init-cols
'((1 #t column-number #f uint)
(2 #f primary-key? #f boolean)
(3 #f column-name #f symbol)
(4 #f column-integrity-rule #f expression)
(5 #f domain-name #f domain)))
(define columns:primary?-pos 2)
(define columns:name-pos 3)
(define columns:integrity-rule-pos 4)
(define columns:domain-name-pos 5)
(define domains:init-cols
'((1 #t domain-name #f atom)
(2 #f foreign-table #f atom)
(3 #f domain-integrity-rule #f expression)
(4 #f type-id #f type)
(5 #f type-param #f expression)))
(define domains:foreign-pos 2)
(define domains:integrity-rule-pos 3)
(define domains:type-id-pos 4)
(define domains:type-param-pos 5)
(define domains:init-data
`((atom #f
(lambda (x) (or (not x) (symbol? x) (number? x)))
atom
#f)
(type #f
#f ;type checked when openning
symbol
#f)
(base-id #f
(lambda (x) (or (symbol? x) (number? x)))
base-id
#f)
(uint #f
(lambda (x)
(and (number? x)
(integer? x)
(not (negative? x))))
integer
#f)
(expression #f #f expression #f)
(boolean #f boolean? boolean #f)
(symbol #f symbol? symbol #f)
(string #f string? string #f)
(domain ,rdms:domains-name #f atom #f)))
(define (rdms:warn . args) (require 'debug) (apply print args))
(define rdms:error slib:error)
(define (make-relational-system base)
(define basic
(lambda (name)
(let ((meth (base name)))
(cond ((not meth) (rdms:error 'make-relational-system
"essential method missing for:" name)))
meth)))
(define (desc-row-type row)
(let ((domain (assq (car (cddddr row)) domains:init-data)))
(and domain (cadddr domain))))
(let ((make-base (base 'make-base))
(open-base (basic 'open-base))
(write-base (base 'write-base))
(sync-base (base 'sync-base))
(close-base (basic 'close-base))
(base:supported-type? (basic 'supported-type?))
(base:supported-key-type? (basic 'supported-key-type?))
(base:make-table (base 'make-table))
(base:open-table (basic 'open-table))
(base:kill-table (base 'kill-table))
(present? (basic 'present?))
(base:ordered-for-each-key (basic 'ordered-for-each-key))
(base:for-each-primary-key (basic 'for-each-key))
(base:map-primary-key (basic 'map-key))
(base:catalog-id (basic 'catalog-id))
(cat:keyify-1 ((basic 'make-keyifier-1)
(desc-row-type (assv 1 catalog:init-cols)))))
(define (init-tab lldb id descriptor rows)
(let ((han (base:open-table lldb id 1 (itypes descriptor)))
(keyify-1
((base 'make-keyifier-1) (desc-row-type (assv 1 descriptor))))
(putter ((basic 'make-putter) 1 (itypes descriptor))))
(for-each (lambda (row) (putter han (keyify-1 (car row)) (cdr row)))
rows)))
(define (itypes rows)
(map (lambda (row)
(let ((domrow (assq (car (cddddr row)) domains:init-data)))
(cond (domrow (cadddr domrow))
(else (rdms:error 'itypes "type not found for:"
(car (cddddr row)))))))
rows))
(define cat:get-row
(let ((cat:getter ((basic 'make-getter) 1 (itypes catalog:init-cols))))
(lambda (bastab key)
(cat:getter bastab (cat:keyify-1 key)))))
(define dom:get-row
(let ((dom:getter ((basic 'make-getter) 1 (itypes domains:init-cols)))
(dom:keyify-1 ((basic 'make-keyifier-1)
(desc-row-type (assv 1 domains:init-cols)))))
(lambda (bastab key)
(dom:getter bastab (dom:keyify-1 key)))))
(define des:get-row
(let ((des:getter ((basic 'make-getter) 1 (itypes columns:init-cols)))
(des:keyify-1 ((basic 'make-keyifier-1)
(desc-row-type (assv 1 columns:init-cols)))))
(lambda (bastab key)
(des:getter bastab (des:keyify-1 key)))))
(define (create-database filename)
(cond ((file-exists? filename)
(rdms:warn 'create-database "file exists:" filename)))
(let* ((lldb (make-base filename 1 (itypes catalog:init-cols)))
(cattab (and lldb (base:open-table lldb base:catalog-id 1
(itypes catalog:init-cols)))))
(cond
((not lldb) (rdms:error 'make-base "failed.") #f)
((not cattab) (rdms:error 'make-base "catalog missing.")
(close-base lldb)
#f)
(else
(let ((desdes-id (base:make-table lldb 1 (itypes columns:init-cols)))
(domdes-id (base:make-table lldb 1 (itypes columns:init-cols)))
(catdes-id (base:make-table lldb 1 (itypes columns:init-cols)))
(domtab-id (base:make-table lldb 1 (itypes domains:init-cols))))
(cond
((not (and catdes-id domdes-id domtab-id desdes-id))
(rdms:error 'create-database "make-table failed.")
(close-base lldb)
#f)
(else
(init-tab lldb desdes-id columns:init-cols columns:init-cols)
(init-tab lldb domdes-id columns:init-cols domains:init-cols)
(init-tab lldb catdes-id columns:init-cols catalog:init-cols)
(init-tab lldb domtab-id domains:init-cols domains:init-data)
(init-tab
lldb base:catalog-id catalog:init-cols
`((*catalog-desc* 5 ,rdms:columns-name ,catdes-id #f #f)
(*domains-desc* 5 ,rdms:columns-name ,domdes-id #f #f)
(,rdms:catalog-name 6 *catalog-desc* ,base:catalog-id #f #f)
(,rdms:domains-name 5 *domains-desc* ,domtab-id #f #f)
(,rdms:columns-name 5 ,rdms:columns-name ,desdes-id #f #f)))
(init-database
filename #t lldb cattab
(base:open-table lldb domtab-id 1 (itypes domains:init-cols))
#f #f))))))))
(define (base:catalog->domains lldb base:catalog)
(let ((cat:row (cat:get-row base:catalog rdms:domains-name)))
(and cat:row
(base:open-table lldb
(list-ref cat:row (+ -2 catalog:bastab-id-pos))
1 (itypes domains:init-cols)))))
(define (open-database filename writable)
(let* ((lldb (open-base filename writable))
(base:catalog
(and lldb (base:open-table lldb base:catalog-id
1 (itypes catalog:init-cols))))
(base:domains
(and base:catalog (base:catalog->domains lldb base:catalog))))
(cond
((not lldb) #f)
((not base:domains) (close-base lldb) #f)
(else (init-database
filename writable lldb base:catalog base:domains #f #f)))))
(define (init-database rdms:filename writable lldb
base:catalog base:domains rdms:catalog rdms:domains)
(define (write-database filename)
(write-base lldb filename)
(set! rdms:filename filename))
(define (close-database)
(close-base lldb)
(set! rdms:filename #f)
(set! base:catalog #f)
(set! base:domains #f)
(set! rdms:catalog #f)
(set! rdms:domains #f))
(define row-ref (lambda (row pos) (list-ref row (+ -2 pos))))
(define row-eval (lambda (row pos)
(let ((ans (list-ref row (+ -2 pos))))
(and ans (slib:eval ans)))))
(define (open-table table-name writable)
(define cat:row (cat:get-row base:catalog table-name))
(let ((column-limit (row-ref cat:row catalog:column-limit-pos))
(desc-table
(base:open-table
lldb
(row-ref (cat:get-row
base:catalog
(row-ref cat:row catalog:coltab-name-pos))
catalog:bastab-id-pos)
1 (itypes columns:init-cols)))
(base-table #f)
(base:get #f)
(primary-limit 1)
(column-name-alist '())
(column-foreign-list '())
(column-domain-list '())
(column-type-list '())
(export-alist '())
(cirs '())
(dirs '())
(list->key #f)
(key->list #f))
(if (not desc-table)
(rdms:error "descriptor table doesn't exist for:" table-name))
(do ((ci column-limit (+ -1 ci)))
((zero? ci))
(let* ((des:row (des:get-row desc-table ci))
(column-name (row-ref des:row columns:name-pos))
(column-domain (row-ref des:row columns:domain-name-pos)))
(set! cirs
(cons (row-eval des:row columns:integrity-rule-pos) cirs))
(set! column-name-alist
(cons (cons column-name ci) column-name-alist))
(cond
(column-domain
(let ((dom:row (dom:get-row base:domains column-domain)))
(set! dirs
(cons (row-eval dom:row domains:integrity-rule-pos)
dirs))
(set! column-type-list
(cons (row-ref dom:row domains:type-id-pos)
column-type-list))
(set! column-domain-list
(cons column-domain column-domain-list))
(set! column-foreign-list
(cons
(let ((foreign-name
(row-ref dom:row domains:foreign-pos)))
(cond
((or (not foreign-name)
(eq? foreign-name table-name)) #f)
(else
(let* ((tab (open-table foreign-name #f))
(p? (and tab (tab 'get 1))))
(cond
((not tab)
(rdms:error "foreign key table missing for:"
foreign-name))
((not (= (tab 'primary-limit) 1))
(rdms:error "foreign key table wrong type:"
foreign-name))
(else p?))))))
column-foreign-list))))
(else
(rdms:error "missing domain for column:" ci column-name)))
(cond
((row-ref des:row columns:primary?-pos)
(set! primary-limit (max primary-limit ci))
(cond
((base:supported-key-type? (car column-type-list)))
(else (rdms:error "key type not supported by base tables:"
(car column-type-list)))))
((base:supported-type? (car column-type-list)))
(else (rdms:error "type not supported by base tables:"
(car column-type-list))))))
(set! base-table
(base:open-table lldb (row-ref cat:row catalog:bastab-id-pos)
primary-limit column-type-list))
(set! base:get ((basic 'make-getter) primary-limit column-type-list))
(set! list->key
((basic 'make-list-keyifier) primary-limit column-type-list))
(set! key->list
((basic 'make-key->list) primary-limit column-type-list))
(let ((export-method
(lambda (name proc)
(set! export-alist
(cons (cons name proc) export-alist))))
(generalize-to-table
(lambda (operation)
(lambda ()
(base:for-each-primary-key base-table operation))))
(accumulate-over-table
(lambda (operation)
(lambda () (base:map-primary-key base-table operation))))
(ckey:retrieve ;ckey gets whole row (assumes exists)
(if (= primary-limit column-limit) key->list
(lambda (ckey) (append (key->list ckey)
(base:get base-table ckey))))))
(export-method
'row:retrieve
(if (= primary-limit column-limit)
(lambda keys
(let ((ckey (list->key keys)))
(and (present? base-table ckey) keys)))
(lambda keys
(let ((vals (base:get base-table (list->key keys))))
(and vals (append keys vals))))))
(export-method 'row:retrieve*
(accumulate-over-table
(if (= primary-limit column-limit) key->list
ckey:retrieve)))
(export-method
'for-each-row
(let ((r (if (= primary-limit column-limit) key->list
ckey:retrieve)))
(lambda (proc) (base:ordered-for-each-key
base-table (lambda (ckey) (proc (r ckey)))))))
(cond
(writable
(letrec
((combine-primary-keys
(cond
((and (= primary-limit column-limit)
(> primary-limit 0))
list->key)
((eq? list->key car) list->key)
(else
(case primary-limit
((1) (let ((keyify-1 ((base 'make-keyifier-1)
(car column-type-list))))
(lambda (row) (keyify-1 (car row)))))
((2) (lambda (row)
(list->key (list (car row) (cadr row)))))
((3) (lambda (row)
(list->key (list (car row) (cadr row)
(caddr row)))))
((4) (lambda (row)
(list->key
(list (car row) (cadr row)
(caddr row) (cadddr row)))))
(else (rdms:error 'combine-primary-keys
"bad number of primary keys"
primary-limit))))))
(uir (row-eval cat:row catalog:integrity-rule-pos))
(check-rules
(lambda (row)
(if (= column-limit (length row)) #t
(rdms:error "bad row length:" row))
(for-each
(lambda (cir dir value column-name column-domain foreign)
(cond
((and dir (not (dir value)))
(rdms:error "violated domain integrity rule:"
table-name column-name
column-domain value))
((and cir (not (cir value)))
(rdms:error "violated column integrity rule:"
table-name column-name value))
((and foreign (not (foreign value)))
(rdms:error "foreign key missing:"
table-name column-name value))))
cirs dirs row
column-name-alist column-domain-list column-foreign-list)
(cond ((and uir (not (uir row)))
(rdms:error "violated user integrity rule:"
row)))))
(putter
((basic 'make-putter) primary-limit column-type-list))
(row:insert
(lambda (row)
(check-rules row)
(let ((ckey (combine-primary-keys row)))
(if (present? base-table ckey)
(rdms:error 'row:insert "row present:" row))
(putter base-table ckey
(list-tail row primary-limit)))))
(row:update
(lambda (row)
(check-rules row)
(putter base-table (combine-primary-keys row)
(list-tail row primary-limit)))))
(export-method 'row:insert row:insert)
(export-method 'row:insert*
(lambda (rows) (for-each row:insert rows)))
(export-method 'row:update row:update)
(export-method 'row:update*
(lambda (rows) (for-each row:update rows))))
(letrec ((base:delete (basic 'delete))
(ckey:remove (lambda (ckey)
(let ((r (ckey:retrieve ckey)))
(and r (base:delete base-table ckey))
r))))
(export-method 'row:remove
(lambda keys
(let ((ckey (list->key keys)))
(and (present? base-table ckey)
(ckey:remove ckey)))))
(export-method 'row:delete
(lambda keys
(base:delete base-table (list->key keys))))
(export-method 'row:remove*
(accumulate-over-table ckey:remove))
(export-method 'row:delete*
(generalize-to-table
(lambda (ckey) (base:delete base-table ckey))))
(export-method 'close-table
(lambda () (set! base-table #f)
(set! desc-table #f)
(set! export-alist #f))))))
(export-method 'column-names (map car column-name-alist))
(export-method 'column-foreigns column-foreign-list)
(export-method 'column-domains column-domain-list)
(export-method 'column-types column-type-list)
(export-method 'primary-limit primary-limit)
(let ((translate-column
(lambda (column)
;;(print 'translate-column column column-name-alist)
(let ((colp (assq column column-name-alist)))
(cond (colp (cdr colp))
((and (number? column)
(integer? column)
(<= 1 column column-limit))
column)
(else (rdms:error "column not in table:"
column table-name)))))))
(lambda args
(cond
((null? args) #f)
((null? (cdr args))
(let ((pp (assq (car args) export-alist)))
(and pp (cdr pp))))
((not (null? (cddr args)))
(rdms:error "too many arguments to methods:" args))
(else
(let ((ci (translate-column (cadr args))))
(cond
((<= ci primary-limit) ;primary-key?
(let ((key-extractor
((base 'make-key-extractor)
primary-limit column-type-list ci)))
(case (car args)
((get) (lambda keys
(and (present? base-table (list->key keys))
(list-ref keys (+ -1 ci)))))
((get*) (lambda ()
(base:map-primary-key
base-table
(lambda (ckey) (key-extractor ckey)))))
(else #f))))
(else
(let ((index (- ci (+ 1 primary-limit))))
(case (car args)
((get) (lambda keys
(let ((row (base:get base-table
(list->key keys))))
(and row (list-ref row index)))))
((get*) (lambda ()
(base:map-primary-key
base-table
(lambda (ckey)
(list-ref (base:get base-table ckey)
index)))))
(else #f)))))))))))))
(define (create-table table-name . desc)
(if (not rdms:catalog)
(set! rdms:catalog (open-table rdms:catalog-name #t)) #f)
(cond
((table-exists? table-name)
(rdms:error "table already exists:" table-name) #f)
((null? desc)
(let ((colt-id (base:make-table lldb 1 (itypes columns:init-cols))))
((rdms:catalog 'row:insert)
(list table-name
(length columns:init-cols)
((rdms:catalog 'get 'coltab-name)
rdms:columns-name)
colt-id
#f
#f)))
(open-table table-name #t))
((null? (cdr desc))
(set! desc (car desc))
(let ((colt-id ((rdms:catalog 'get 'bastab-id) desc)))
(cond
(colt-id
(let ((coltable (open-table desc #f))
(types '())
(prilimit 0)
(colimit 0)
(colerr #f))
(for-each (lambda (n p d)
(if (number? n) (set! colimit (max colimit n))
(set! colerr #t))
(if p (set! prilimit (+ 1 prilimit)) #f)
(set! types (cons
(dom:get-row base:domains d) types)))
((coltable 'get* 'column-number))
((coltable 'get* 'primary-key?))
((coltable 'get* 'domain-name)))
(cond (colerr (rdms:error "some column lacks a number.") #f)
((or (< prilimit 1)
(and (> prilimit 4)
(not (= prilimit colimit))))
(rdms:error "unreasonable number of primary keys:"
prilimit))
(else
((rdms:catalog 'row:insert)
(list table-name colimit desc
(base:make-table lldb prilimit types) #f #f))
(open-table table-name #t)))))
(else
(rdms:error "table descriptor not found for:" desc) #f))))
(else (rdms:error 'create-table "too many args:"
(cons table-name desc))
#f)))
(define (table-exists? table-name)
(present? base:catalog (cat:keyify-1 table-name)))
(define (delete-table table-name)
(if (not rdms:catalog)
(set! rdms:catalog (open-table rdms:catalog-name #t)) #f)
(let ((table (open-table table-name #t))
(row ((rdms:catalog 'row:remove) table-name)))
(and row (base:kill-table
lldb
(list-ref row (+ -1 catalog:bastab-id-pos))
(table 'primary-limit)
(table 'column-type-list))
row)))
(define (delete-domain domain-name)
(if (not rdms:domains)
(set! rdms:domains (open-table rdms:domains-name #t)) #f)
((rdms:domains 'row:remove) domain-name))
(define (add-domain domain-row)
(if (not rdms:domains)
(set! rdms:domains (open-table rdms:domains-name #t)) #f)
((rdms:domains 'row:insert) domain-row))
(lambda (operation-name)
(case operation-name
((close-database) close-database)
((write-database) write-database)
((open-table) open-table)
((delete-table) delete-table)
((create-table) create-table)
((table-exists?) table-exists?)
((add-domain) add-domain)
((delete-domain) delete-domain)
(else #f)))
)
(lambda (operation-name)
(case operation-name
((create-database) create-database)
((open-database) open-database)
(else #f)))
))