sql/expressions.lisp

   1 ;;;; -*- Mode: LISP; Syntax: ANSI-Common-Lisp; Base: 10 -*-
   2 ;;;; *************************************************************************
   3 ;;;;
   4 ;;;; $Id$
   5 ;;;;
   6 ;;;; Classes defining SQL expressions and methods for formatting the
   7 ;;;; appropriate SQL commands.
   8 ;;;;
   9 ;;;; This file is part of CLSQL.
  10 ;;;;
  11 ;;;; CLSQL users are granted the rights to distribute and use this software
  12 ;;;; as governed by the terms of the Lisp Lesser GNU Public License
  13 ;;;; (http://opensource.franz.com/preamble.html), also known as the LLGPL.
  14 ;;;; *************************************************************************
  15
  16 (in-package #:clsql-sys)
  17
  18 (defvar +empty-string+ "''")
  19
  20 (defvar +null-string+ "NULL")
  21
  22 (defvar *sql-stream* nil
  23   "stream which accumulates SQL output")
  24
  25 (defun sql-output (sql-expr &optional (database *default-database*))
  26   "Top-level call for generating SQL strings. Returns an SQL
  27   string appropriate for DATABASE which corresponds to the
  28   supplied lisp expression SQL-EXPR."
  29   (progv '(*sql-stream*)
  30       `(,(make-string-output-stream))
  31     (output-sql sql-expr database)
  32     (get-output-stream-string *sql-stream*)))
  33
  34 (defmethod output-sql (expr database)
  35   (write-string (database-output-sql expr database) *sql-stream*)
  36   (values))
  37
  38 (defvar *output-hash* (make-hash-table :test #'equal)
  39   "For caching generated SQL strings.")
  40
  41 (defmethod output-sql :around ((sql t) database)
  42   (let* ((hash-key (output-sql-hash-key sql database))
  43          (hash-value (when hash-key (gethash hash-key *output-hash*))))
  44     (cond ((and hash-key hash-value)
  45            (write-string hash-value *sql-stream*))
  46           (hash-key
  47            (let ((*sql-stream* (make-string-output-stream)))
  48              (call-next-method)
  49              (setf hash-value (get-output-stream-string *sql-stream*))
  50              (setf (gethash hash-key *output-hash*) hash-value))
  51            (write-string hash-value *sql-stream*))
  52           (t
  53            (call-next-method)))))
  54
  55 (defmethod output-sql-hash-key (expr database)
  56   (declare (ignore expr database))
  57   nil)
  58
  59
  60 (defclass %sql-expression ()
  61   ())
  62
  63 (defmethod output-sql ((expr %sql-expression) database)
  64   (declare (ignore database))
  65   (write-string +null-string+ *sql-stream*))
  66
  67 (defmethod print-object ((self %sql-expression) stream)
  68   (print-unreadable-object
  69    (self stream :type t)
  70    (write-string (sql-output self) stream))
  71   self)
  72
  73 ;; For straight up strings
  74
  75 (defclass sql (%sql-expression)
  76   ((text
  77     :initarg :string
  78     :initform ""))
  79   (:documentation "A literal SQL expression."))
  80
  81 (defmethod make-load-form ((sql sql) &optional environment)
  82   (declare (ignore environment))
  83   (with-slots (text)
  84     sql
  85     `(make-instance 'sql :string ',text)))
  86
  87 (defmethod output-sql ((expr sql) database)
  88   (declare (ignore database))
  89   (write-string (slot-value expr 'text) *sql-stream*)
  90   t)
  91
  92 (defmethod print-object ((ident sql) stream)
  93   (format stream "#<~S \"~A\">"
  94           (type-of ident)
  95           (sql-output ident nil))
  96   ident)
  97
  98 ;; For SQL Identifiers of generic type
  99
 100 (defclass sql-ident (%sql-expression)
 101   ((name
 102     :initarg :name
 103     :initform +null-string+))
 104   (:documentation "An SQL identifer."))
 105
 106 (defmethod make-load-form ((sql sql-ident) &optional environment)
 107   (declare (ignore environment))
 108   (with-slots (name)
 109     sql
 110     `(make-instance 'sql-ident :name ',name)))
 111
 112 (defmethod output-sql ((expr sql-ident) database)
 113   (with-slots (name) expr
 114     (write-string
 115      (etypecase name
 116        (string name)
 117        (symbol (symbol-name name) database))
 118      *sql-stream*))
 119   t)
 120
 121 ;; For SQL Identifiers for attributes
 122
 123 (defclass sql-ident-attribute (sql-ident)
 124   ((qualifier
 125     :initarg :qualifier
 126     :initform +null-string+)
 127    (type
 128     :initarg :type
 129     :initform +null-string+))
 130   (:documentation "An SQL Attribute identifier."))
 131
 132 (defmethod collect-table-refs (sql)
 133   (declare (ignore sql))
 134   nil)
 135
 136 (defmethod collect-table-refs ((sql sql-ident-attribute))
 137   (let ((qual (slot-value sql 'qualifier)))
 138     (when qual
 139       (list (make-instance 'sql-ident-table :name qual)))))
 140
 141 (defmethod make-load-form ((sql sql-ident-attribute) &optional environment)
 142   (declare (ignore environment))
 143   (with-slots (qualifier type name)
 144     sql
 145     `(make-instance 'sql-ident-attribute :name ',name
 146       :qualifier ',qualifier
 147       :type ',type)))
 148
 149 (defmethod output-sql ((expr sql-ident-attribute) database)
 150   (with-slots (qualifier name type) expr
 151     (if (and (not qualifier) (not type))
 152         (etypecase name
 153           (string
 154            (write-string name *sql-stream*))
 155           (symbol
 156            (write-string
 157             (sql-escape (symbol-name name)) *sql-stream*)))
 158
 159         ;;; KMR: The TYPE field is used by CommonSQL for type conversion -- it
 160       ;;; should not be output in SQL statements
 161       #+ignore
 162       (format *sql-stream* "~@[~A.~]~A~@[ ~A~]"
 163               (when qualifier
 164                 (sql-escape qualifier))
 165               (sql-escape name)
 166               (when type
 167                 (symbol-name type)))
 168       (format *sql-stream* "~@[~A.~]~A"
 169               (when qualifier
 170                 (typecase qualifier
 171                   (string (format nil "~s" qualifier))
 172                   (t (sql-escape qualifier))))
 173               (typecase name
 174                 (string (format nil "~s" (sql-escape name)))
 175                 (t (sql-escape name)))))
 176     t))
 177
 178 (defmethod output-sql-hash-key ((expr sql-ident-attribute) database)
 179   (with-slots (qualifier name type)
 180       expr
 181     (list (and database (database-underlying-type database))
 182           'sql-ident-attribute qualifier name type)))
 183
 184 ;; For SQL Identifiers for tables
 185
 186 (defclass sql-ident-table (sql-ident)
 187   ((alias
 188     :initarg :table-alias :initform nil))
 189   (:documentation "An SQL table identifier."))
 190
 191 (defmethod make-load-form ((sql sql-ident-table) &optional environment)
 192   (declare (ignore environment))
 193   (with-slots (alias name)
 194     sql
 195     `(make-instance 'sql-ident-table :name ',name :table-alias ',alias)))
 196
 197 (defmethod output-sql ((expr sql-ident-table) database)
 198   (with-slots (name alias) expr
 199     (etypecase name
 200       (string
 201        (format *sql-stream* "~s" (sql-escape name)))
 202       (symbol
 203        (write-string (sql-escape name) *sql-stream*)))
 204     (when alias
 205       (format *sql-stream* " ~s" alias)))
 206   t)
 207
 208 (defmethod output-sql-hash-key ((expr sql-ident-table) database)
 209   (with-slots (name alias)
 210       expr
 211     (list (and database (database-underlying-type database))
 212           'sql-ident-table name alias)))
 213
 214 (defclass sql-relational-exp (%sql-expression)
 215   ((operator
 216     :initarg :operator
 217     :initform nil)
 218    (sub-expressions
 219     :initarg :sub-expressions
 220     :initform nil))
 221   (:documentation "An SQL relational expression."))
 222
 223 (defmethod make-load-form ((self sql-relational-exp) &optional environment)
 224   (make-load-form-saving-slots self
 225                                :slot-names '(operator sub-expressions)
 226                                :environment environment))
 227
 228 (defmethod collect-table-refs ((sql sql-relational-exp))
 229   (let ((tabs nil))
 230     (dolist (exp (slot-value sql 'sub-expressions))
 231       (let ((refs (collect-table-refs exp)))
 232         (if refs (setf tabs (append refs tabs)))))
 233     (remove-duplicates tabs
 234                        :test (lambda (tab1 tab2)
 235                                (equal (slot-value tab1 'name)
 236                                       (slot-value tab2 'name))))))
 237
 238
 239
 240
 241 ;; Write SQL for relational operators (like 'AND' and 'OR').
 242 ;; should do arity checking of subexpressions
 243
 244 (defmethod output-sql ((expr sql-relational-exp) database)
 245   (with-slots (operator sub-expressions)
 246     expr
 247     (let ((subs (if (consp (car sub-expressions))
 248                     (car sub-expressions)
 249                     sub-expressions)))
 250       (write-char #\( *sql-stream*)
 251       (do ((sub subs (cdr sub)))
 252           ((null (cdr sub)) (output-sql (car sub) database))
 253         (output-sql (car sub) database)
 254         (write-char #\Space *sql-stream*)
 255         (output-sql operator database)
 256         (write-char #\Space *sql-stream*))
 257       (write-char #\) *sql-stream*)))
 258   t)
 259
 260 (defclass sql-upcase-like (sql-relational-exp)
 261   ()
 262   (:documentation "An SQL 'like' that upcases its arguments."))
 263
 264 (defmethod output-sql ((expr sql-upcase-like) database)
 265   (flet ((write-term (term)
 266            (write-string "upper(" *sql-stream*)
 267            (output-sql term database)
 268            (write-char #\) *sql-stream*)))
 269     (with-slots (sub-expressions)
 270       expr
 271       (let ((subs (if (consp (car sub-expressions))
 272                       (car sub-expressions)
 273                       sub-expressions)))
 274         (write-char #\( *sql-stream*)
 275         (do ((sub subs (cdr sub)))
 276             ((null (cdr sub)) (write-term (car sub)))
 277           (write-term (car sub))
 278           (write-string " LIKE " *sql-stream*))
 279         (write-char #\) *sql-stream*))))
 280   t)
 281
 282 (defclass sql-assignment-exp (sql-relational-exp)
 283   ()
 284   (:documentation "An SQL Assignment expression."))
 285
 286
 287 (defmethod output-sql ((expr sql-assignment-exp) database)
 288   (with-slots (operator sub-expressions)
 289     expr
 290     (do ((sub sub-expressions (cdr sub)))
 291         ((null (cdr sub)) (output-sql (car sub) database))
 292       (output-sql (car sub) database)
 293       (write-char #\Space *sql-stream*)
 294       (output-sql operator database)
 295       (write-char #\Space *sql-stream*)))
 296   t)
 297
 298 (defclass sql-value-exp (%sql-expression)
 299   ((modifier
 300     :initarg :modifier
 301     :initform nil)
 302    (components
 303     :initarg :components
 304     :initform nil))
 305   (:documentation
 306    "An SQL value expression.")
 307   )
 308
 309 (defmethod collect-table-refs ((sql sql-value-exp))
 310   (let ((tabs nil))
 311     (if (listp (slot-value sql 'components))
 312         (progn
 313           (dolist (exp (slot-value sql 'components))
 314             (let ((refs (collect-table-refs exp)))
 315               (if refs (setf tabs (append refs tabs)))))
 316           (remove-duplicates tabs
 317                              :test (lambda (tab1 tab2)
 318                                      (equal (slot-value tab1 'name)
 319                                             (slot-value tab2 'name)))))
 320         nil)))
 321
 322
 323
 324 (defmethod output-sql ((expr sql-value-exp) database)
 325   (with-slots (modifier components)
 326     expr
 327     (if modifier
 328         (progn
 329           (write-char #\( *sql-stream*)
 330           (output-sql modifier database)
 331           (write-char #\Space *sql-stream*)
 332           (output-sql components database)
 333           (write-char #\) *sql-stream*))
 334         (output-sql components database))))
 335
 336 (defclass sql-typecast-exp (sql-value-exp)
 337   ()
 338   (:documentation "An SQL typecast expression."))
 339
 340 (defmethod output-sql ((expr sql-typecast-exp) database)
 341   (with-slots (components)
 342     expr
 343     (output-sql components database)))
 344
 345 (defmethod collect-table-refs ((sql sql-typecast-exp))
 346   (when (slot-value sql 'components)
 347     (collect-table-refs (slot-value sql 'components))))
 348
 349 (defclass sql-function-exp (%sql-expression)
 350   ((name
 351     :initarg :name
 352     :initform nil)
 353    (args
 354     :initarg :args
 355     :initform nil))
 356   (:documentation
 357    "An SQL function expression."))
 358
 359 (defmethod collect-table-refs ((sql sql-function-exp))
 360   (let ((tabs nil))
 361     (dolist (exp (slot-value sql 'args))
 362       (let ((refs (collect-table-refs exp)))
 363         (if refs (setf tabs (append refs tabs)))))
 364     (remove-duplicates tabs
 365                        :test (lambda (tab1 tab2)
 366                                (equal (slot-value tab1 'name)
 367                                       (slot-value tab2 'name))))))
 368 (defvar *in-subselect* nil)
 369
 370 (defmethod output-sql ((expr sql-function-exp) database)
 371   (with-slots (name args)
 372     expr
 373     (output-sql name database)
 374     (let ((*in-subselect* nil)) ;; aboid double parens
 375       (when args (output-sql args database))))
 376   t)
 377
 378
 379 (defclass sql-between-exp (sql-function-exp)
 380   ()
 381   (:documentation "An SQL between expression."))
 382
 383 (defmethod output-sql ((expr sql-between-exp) database)
 384   (with-slots (args)
 385       expr
 386     (output-sql (first args) database)
 387     (write-string " BETWEEN " *sql-stream*)
 388     (output-sql (second args) database)
 389     (write-string " AND " *sql-stream*)
 390     (output-sql (third args) database))
 391   t)
 392
 393 (defclass sql-query-modifier-exp (%sql-expression)
 394   ((modifier :initarg :modifier :initform nil)
 395    (components :initarg :components :initform nil))
 396   (:documentation "An SQL query modifier expression."))
 397
 398 (defmethod output-sql ((expr sql-query-modifier-exp) database)
 399   (with-slots (modifier components)
 400       expr
 401     (output-sql modifier database)
 402     (write-string " " *sql-stream*)
 403     (output-sql (car components) database)
 404     (when components
 405       (mapc #'(lambda (comp)
 406                 (write-string ", " *sql-stream*)
 407                 (output-sql comp database))
 408             (cdr components))))
 409   t)
 410
 411 (defclass sql-set-exp (%sql-expression)
 412   ((operator
 413     :initarg :operator
 414     :initform nil)
 415    (sub-expressions
 416     :initarg :sub-expressions
 417     :initform nil))
 418   (:documentation "An SQL set expression."))
 419
 420 (defmethod collect-table-refs ((sql sql-set-exp))
 421   (let ((tabs nil))
 422     (dolist (exp (slot-value sql 'sub-expressions))
 423       (let ((refs (collect-table-refs exp)))
 424         (if refs (setf tabs (append refs tabs)))))
 425     (remove-duplicates tabs
 426                        :test (lambda (tab1 tab2)
 427                                (equal (slot-value tab1 'name)
 428                                       (slot-value tab2 'name))))))
 429
 430 (defmethod output-sql ((expr sql-set-exp) database)
 431   (with-slots (operator sub-expressions)
 432       expr
 433     (let ((subs (if (consp (car sub-expressions))
 434                     (car sub-expressions)
 435                     sub-expressions)))
 436       (when (= (length subs) 1)
 437         (output-sql operator database)
 438         (write-char #\Space *sql-stream*))
 439       (do ((sub subs (cdr sub)))
 440           ((null (cdr sub)) (output-sql (car sub) database))
 441         (output-sql (car sub) database)
 442         (write-char #\Space *sql-stream*)
 443         (output-sql operator database)
 444         (write-char #\Space *sql-stream*))))
 445   t)
 446
 447 (defclass sql-query (%sql-expression)
 448   ((selections
 449     :initarg :selections
 450     :initform nil)
 451    (all
 452     :initarg :all
 453     :initform nil)
 454    (flatp
 455     :initarg :flatp
 456     :initform nil)
 457    (set-operation
 458     :initarg :set-operation
 459     :initform nil)
 460    (distinct
 461     :initarg :distinct
 462     :initform nil)
 463    (from
 464     :initarg :from
 465     :initform nil)
 466    (where
 467     :initarg :where
 468     :initform nil)
 469    (group-by
 470     :initarg :group-by
 471     :initform nil)
 472    (having
 473     :initarg :having
 474     :initform nil)
 475    (limit
 476     :initarg :limit
 477     :initform nil)
 478    (offset
 479     :initarg :offset
 480     :initform nil)
 481    (order-by
 482     :initarg :order-by
 483     :initform nil)
 484    (inner-join
 485     :initarg :inner-join
 486     :initform nil)
 487    (on
 488     :initarg :on
 489     :initform nil))
 490   (:documentation "An SQL SELECT query."))
 491
 492 (defclass sql-object-query (%sql-expression)
 493   ((objects
 494     :initarg :objects
 495     :initform nil)
 496    (flatp
 497     :initarg :flatp
 498     :initform nil)
 499    (exp
 500     :initarg :exp
 501     :initform nil)
 502    (refresh
 503     :initarg :refresh
 504     :initform nil)))
 505
 506 (defmethod collect-table-refs ((sql sql-query))
 507   (remove-duplicates (collect-table-refs (slot-value sql 'where))
 508                      :test (lambda (tab1 tab2)
 509                              (equal (slot-value tab1 'name)
 510                                     (slot-value tab2 'name)))))
 511
 512 (defvar *select-arguments*
 513   '(:all :database :distinct :flatp :from :group-by :having :order-by
 514     :set-operation :where :offset :limit :inner-join :on
 515     ;; below keywords are not a SQL argument, but these keywords may terminate select
 516     :caching :refresh))
 517
 518 (defun query-arg-p (sym)
 519   (member sym *select-arguments*))
 520
 521 (defun query-get-selections (select-args)
 522   "Return two values: the list of select-args up to the first keyword,
 523 uninclusive, and the args from that keyword to the end."
 524   (let ((first-key-arg (position-if #'query-arg-p select-args)))
 525     (if first-key-arg
 526         (values (subseq select-args 0 first-key-arg)
 527                 (subseq select-args first-key-arg))
 528         select-args)))
 529
 530 (defun make-query (&rest args)
 531   (flet ((select-objects (target-args)
 532            (and target-args
 533                 (every #'(lambda (arg)
 534                            (and (symbolp arg)
 535                                 (find-class arg nil)))
 536                        target-args))))
 537     (multiple-value-bind (selections arglist)
 538         (query-get-selections args)
 539       (if (select-objects selections)
 540           (destructuring-bind (&key flatp refresh &allow-other-keys) arglist
 541             (make-instance 'sql-object-query :objects selections
 542                            :flatp flatp :refresh refresh
 543                            :exp arglist))
 544           (destructuring-bind (&key all flatp set-operation distinct from where
 545                                     group-by having order-by
 546                                     offset limit inner-join on &allow-other-keys)
 547               arglist
 548             (if (null selections)
 549                 (error "No target columns supplied to select statement."))
 550             (if (null from)
 551                 (error "No source tables supplied to select statement."))
 552             (make-instance 'sql-query :selections selections
 553                            :all all :flatp flatp :set-operation set-operation
 554                            :distinct distinct :from from :where where
 555                            :limit limit :offset offset
 556                            :group-by group-by :having having :order-by order-by
 557                            :inner-join inner-join :on on))))))
 558
 559 (defmethod output-sql ((query sql-query) database)
 560   (with-slots (distinct selections from where group-by having order-by
 561                         limit offset inner-join on all set-operation)
 562       query
 563     (when *in-subselect*
 564       (write-string "(" *sql-stream*))
 565     (write-string "SELECT " *sql-stream*)
 566     (when all
 567       (write-string "ALL " *sql-stream*))
 568     (when (and distinct (not all))
 569       (write-string "DISTINCT " *sql-stream*)
 570       (unless (eql t distinct)
 571         (write-string "ON " *sql-stream*)
 572         (output-sql distinct database)
 573         (write-char #\Space *sql-stream*)))
 574     (output-sql (apply #'vector selections) database)
 575     (when from
 576       (write-string " FROM " *sql-stream*)
 577       (flet ((ident-table-equal (a b)
 578                (and (if (and (eql (type-of a) 'sql-ident-table)
 579                              (eql (type-of b) 'sql-ident-table))
 580                         (string-equal (slot-value a 'alias)
 581                                       (slot-value b 'alias))
 582                         t)
 583                     (string-equal (sql-escape (slot-value a 'name))
 584                                   (sql-escape (slot-value b 'name))))))
 585         (typecase from
 586           (list (output-sql (apply #'vector
 587                                    (remove-duplicates from
 588                                                       :test #'ident-table-equal))
 589                             database))
 590           (string (format *sql-stream* "~s" (sql-escape from)))
 591           (t (let ((*in-subselect* t))
 592                (output-sql from database))))))
 593     (when inner-join
 594       (write-string " INNER JOIN " *sql-stream*)
 595       (output-sql inner-join database))
 596     (when on
 597       (write-string " ON " *sql-stream*)
 598       (output-sql on database))
 599     (when where
 600       (write-string " WHERE " *sql-stream*)
 601       (let ((*in-subselect* t))
 602         (output-sql where database)))
 603     (when group-by
 604       (write-string " GROUP BY " *sql-stream*)
 605       (if (listp group-by)
 606           (do ((order group-by (cdr order)))
 607               ((null order))
 608             (let ((item (car order)))
 609               (typecase item
 610                 (cons
 611                  (output-sql (car item) database)
 612                  (format *sql-stream* " ~A" (cadr item)))
 613                 (t
 614                  (output-sql item database)))
 615               (when (cdr order)
 616                 (write-char #\, *sql-stream*))))
 617           (output-sql group-by database)))
 618     (when having
 619       (write-string " HAVING " *sql-stream*)
 620       (output-sql having database))
 621     (when order-by
 622       (write-string " ORDER BY " *sql-stream*)
 623       (if (listp order-by)
 624           (do ((order order-by (cdr order)))
 625               ((null order))
 626             (let ((item (car order)))
 627               (typecase item
 628                 (cons
 629                  (output-sql (car item) database)
 630                  (format *sql-stream* " ~A" (cadr item)))
 631                 (t
 632                  (output-sql item database)))
 633               (when (cdr order)
 634                 (write-char #\, *sql-stream*))))
 635           (output-sql order-by database)))
 636     (when limit
 637       (write-string " LIMIT " *sql-stream*)
 638       (output-sql limit database))
 639     (when offset
 640       (write-string " OFFSET " *sql-stream*)
 641       (output-sql offset database))
 642     (when *in-subselect*
 643       (write-string ")" *sql-stream*))
 644     (when set-operation
 645       (write-char #\Space *sql-stream*)
 646       (output-sql set-operation database)))
 647   t)
 648
 649 (defmethod output-sql ((query sql-object-query) database)
 650   (declare (ignore database))
 651   (with-slots (objects)
 652       query
 653     (when objects
 654       (format *sql-stream* "(~{~A~^ ~})" objects))))
 655
 656
 657 ;; INSERT
 658
 659 (defclass sql-insert (%sql-expression)
 660   ((into
 661     :initarg :into
 662     :initform nil)
 663    (attributes
 664     :initarg :attributes
 665     :initform nil)
 666    (values
 667     :initarg :values
 668     :initform nil)
 669    (query
 670     :initarg :query
 671     :initform nil))
 672   (:documentation
 673    "An SQL INSERT statement."))
 674
 675 (defmethod output-sql ((ins sql-insert) database)
 676   (with-slots (into attributes values query)
 677     ins
 678     (write-string "INSERT INTO " *sql-stream*)
 679     (output-sql
 680      (typecase into
 681        (string (sql-expression :table into))
 682        (t into))
 683      database)
 684     (when attributes
 685       (write-char #\Space *sql-stream*)
 686       (output-sql attributes database))
 687     (when values
 688       (write-string " VALUES " *sql-stream*)
 689       (output-sql values database))
 690     (when query
 691       (write-char #\Space *sql-stream*)
 692       (output-sql query database)))
 693   t)
 694
 695 ;; DELETE
 696
 697 (defclass sql-delete (%sql-expression)
 698   ((from
 699     :initarg :from
 700     :initform nil)
 701    (where
 702     :initarg :where
 703     :initform nil))
 704   (:documentation
 705    "An SQL DELETE statement."))
 706
 707 (defmethod output-sql ((stmt sql-delete) database)
 708   (with-slots (from where)
 709     stmt
 710     (write-string "DELETE FROM " *sql-stream*)
 711     (typecase from
 712       ((or symbol string) (write-string (sql-escape from) *sql-stream*))
 713       (t  (output-sql from database)))
 714     (when where
 715       (write-string " WHERE " *sql-stream*)
 716       (output-sql where database)))
 717   t)
 718
 719 ;; UPDATE
 720
 721 (defclass sql-update (%sql-expression)
 722   ((table
 723     :initarg :table
 724     :initform nil)
 725    (attributes
 726     :initarg :attributes
 727     :initform nil)
 728    (values
 729     :initarg :values
 730     :initform nil)
 731    (where
 732     :initarg :where
 733     :initform nil))
 734   (:documentation "An SQL UPDATE statement."))
 735
 736 (defmethod output-sql ((expr sql-update) database)
 737   (with-slots (table where attributes values)
 738     expr
 739     (flet ((update-assignments ()
 740              (mapcar #'(lambda (a b)
 741                          (make-instance 'sql-assignment-exp
 742                                         :operator '=
 743                                         :sub-expressions (list a b)))
 744                      attributes values)))
 745       (write-string "UPDATE " *sql-stream*)
 746       (output-sql table database)
 747       (write-string " SET " *sql-stream*)
 748       (output-sql (apply #'vector (update-assignments)) database)
 749       (when where
 750         (write-string " WHERE " *sql-stream*)
 751         (output-sql where database))))
 752   t)
 753
 754 ;; CREATE TABLE
 755
 756 (defclass sql-create-table (%sql-expression)
 757   ((name
 758     :initarg :name
 759     :initform nil)
 760    (columns
 761     :initarg :columns
 762     :initform nil)
 763    (modifiers
 764     :initarg :modifiers
 765     :initform nil)
 766    (transactions
 767     :initarg :transactions
 768     :initform nil))
 769   (:documentation
 770    "An SQL CREATE TABLE statement."))
 771
 772 ;; Here's a real warhorse of a function!
 773
 774 (declaim (inline listify))
 775 (defun listify (x)
 776   (if (atom x)
 777       (list x)
 778       x))
 779
 780 (defmethod output-sql ((stmt sql-create-table) database)
 781   (flet ((output-column (column-spec)
 782            (destructuring-bind (name type &optional db-type &rest constraints)
 783                column-spec
 784              (let ((type (listify type)))
 785                (output-sql name database)
 786                (write-char #\Space *sql-stream*)
 787                (write-string
 788                 (if (stringp db-type) db-type ; override definition
 789                   (database-get-type-specifier (car type) (cdr type) database
 790                                                (database-underlying-type database)))
 791                 *sql-stream*)
 792                (let ((constraints (database-constraint-statement
 793                                    (if (and db-type (symbolp db-type))
 794                                        (cons db-type constraints)
 795                                        constraints)
 796                                    database)))
 797                  (when constraints
 798                    (write-string " " *sql-stream*)
 799                    (write-string constraints *sql-stream*)))))))
 800     (with-slots (name columns modifiers transactions)
 801       stmt
 802       (write-string "CREATE TABLE " *sql-stream*)
 803       (etypecase name
 804           (string (format *sql-stream* "~s" (sql-escape name)))
 805           (symbol (write-string (sql-escape name) *sql-stream*))
 806           (sql-ident (output-sql name database)))
 807       (write-string " (" *sql-stream*)
 808       (do ((column columns (cdr column)))
 809           ((null (cdr column))
 810            (output-column (car column)))
 811         (output-column (car column))
 812         (write-string ", " *sql-stream*))
 813       (when modifiers
 814         (do ((modifier (listify modifiers) (cdr modifier)))
 815             ((null modifier))
 816           (write-string ", " *sql-stream*)
 817           (write-string (car modifier) *sql-stream*)))
 818       (write-char #\) *sql-stream*)
 819       (when (and (eq :mysql (database-underlying-type database))
 820                  transactions
 821                  (db-type-transaction-capable? :mysql database))
 822         (write-string " Type=InnoDB" *sql-stream*))))
 823   t)
 824
 825
 826 ;; CREATE VIEW
 827
 828 (defclass sql-create-view (%sql-expression)
 829   ((name :initarg :name :initform nil)
 830    (column-list :initarg :column-list :initform nil)
 831    (query :initarg :query :initform nil)
 832    (with-check-option :initarg :with-check-option :initform nil))
 833   (:documentation "An SQL CREATE VIEW statement."))
 834
 835 (defmethod output-sql ((stmt sql-create-view) database)
 836   (with-slots (name column-list query with-check-option) stmt
 837     (write-string "CREATE VIEW " *sql-stream*)
 838     (output-sql name database)
 839     (when column-list (write-string " " *sql-stream*)
 840           (output-sql (listify column-list) database))
 841     (write-string " AS " *sql-stream*)
 842     (output-sql query database)
 843     (when with-check-option (write-string " WITH CHECK OPTION" *sql-stream*))))
 844
 845
 846 ;;
 847 ;; DATABASE-OUTPUT-SQL
 848 ;;
 849
 850 (defmethod database-output-sql ((str string) database)
 851   (declare (optimize (speed 3) (safety 1)
 852                      #+cmu (extensions:inhibit-warnings 3)))
 853   (let ((len (length str)))
 854     (declare (type fixnum len))
 855     (cond ((zerop len)
 856            +empty-string+)
 857           ((and (null (position #\' str))
 858                 (null (position #\\ str)))
 859            (concatenate 'string "'" str "'"))
 860           (t
 861            (let ((buf (make-string (+ (* len 2) 2) :initial-element #\')))
 862              (declare (simple-string buf))
 863              (do* ((i 0 (incf i))
 864                    (j 1 (incf j)))
 865                   ((= i len) (subseq buf 0 (1+ j)))
 866                (declare (type fixnum i j))
 867                (let ((char (aref str i)))
 868                  (declare (character char))
 869                  (cond ((char= char #\')
 870                         (setf (aref buf j) #\')
 871                         (incf j)
 872                         (setf (aref buf j) #\'))
 873                        ((and (char= char #\\)
 874                              ;; MTP: only escape backslash with pgsql/mysql
 875                              (member (database-underlying-type database)
 876                                      '(:postgresql :mysql)
 877                                      :test #'eq))
 878                         (setf (aref buf j) #\\)
 879                         (incf j)
 880                         (setf (aref buf j) #\\))
 881                        (t
 882                         (setf (aref buf j) char))))))))))
 883
 884 (let ((keyword-package (symbol-package :foo)))
 885   (defmethod database-output-sql ((sym symbol) database)
 886   (if (null sym)
 887       +null-string+
 888     (if (equal (symbol-package sym) keyword-package)
 889         (concatenate 'string "'" (string sym) "'")
 890       (symbol-name sym)))))
 891
 892 (defmethod database-output-sql ((tee (eql t)) database)
 893   (if database
 894       (let ((val (database-output-sql-as-type 'boolean t database (database-type database))))
 895         (when val
 896           (typecase val
 897             (string (format nil "'~A'" val))
 898             (integer (format nil "~A" val)))))
 899     "'Y'"))
 900
 901 #+nil(defmethod database-output-sql ((tee (eql t)) database)
 902   (declare (ignore database))
 903   "'Y'")
 904
 905 (defmethod database-output-sql ((num number) database)
 906   (declare (ignore database))
 907   (number-to-sql-string num))
 908
 909 (defmethod database-output-sql ((arg list) database)
 910   (if (null arg)
 911       +null-string+
 912       (format nil "(~{~A~^,~})" (mapcar #'(lambda (val)
 913                                             (sql-output val database))
 914                                         arg))))
 915
 916 (defmethod database-output-sql ((arg vector) database)
 917   (format nil "~{~A~^,~}" (map 'list #'(lambda (val)
 918                                          (sql-output val database))
 919                                arg)))
 920
 921 (defmethod output-sql-hash-key ((arg vector) database)
 922   (list 'vector (map 'list (lambda (arg)
 923                              (or (output-sql-hash-key arg database)
 924                                  (return-from output-sql-hash-key nil)))
 925                      arg)))
 926
 927 (defmethod database-output-sql ((self wall-time) database)
 928   (declare (ignore database))
 929   (db-timestring self))
 930
 931 (defmethod database-output-sql ((self date) database)
 932   (declare (ignore database))
 933   (db-datestring self))
 934
 935 (defmethod database-output-sql ((self duration) database)
 936   (declare (ignore database))
 937   (format nil "'~a'" (duration-timestring self)))
 938
 939 #+ignore
 940 (defmethod database-output-sql ((self money) database)
 941   (database-output-sql (slot-value self 'odcl::units) database))
 942
 943 (defmethod database-output-sql (thing database)
 944   (if (or (null thing)
 945           (eq 'null thing))
 946       +null-string+
 947     (error 'sql-user-error
 948            :message
 949            (format nil
 950                    "No type conversion to SQL for ~A is defined for DB ~A."
 951                    (type-of thing) (type-of database)))))
 952
 953
 954 ;;
 955 ;; Column constraint types and conversion to SQL
 956 ;;
 957
 958 (defparameter *constraint-types*
 959   (list
 960    (cons (symbol-name-default-case "NOT-NULL") "NOT NULL")
 961    (cons (symbol-name-default-case "PRIMARY-KEY") "PRIMARY KEY")
 962    (cons (symbol-name-default-case "NOT") "NOT")
 963    (cons (symbol-name-default-case "NULL") "NULL")
 964    (cons (symbol-name-default-case "PRIMARY") "PRIMARY")
 965    (cons (symbol-name-default-case "KEY") "KEY")
 966    (cons (symbol-name-default-case "UNSIGNED") "UNSIGNED")
 967    (cons (symbol-name-default-case "ZEROFILL") "ZEROFILL")
 968    (cons (symbol-name-default-case "AUTO-INCREMENT") "AUTO_INCREMENT")
 969    (cons (symbol-name-default-case "UNIQUE") "UNIQUE")))
 970
 971 (defmethod database-constraint-statement (constraint-list database)
 972   (declare (ignore database))
 973   (make-constraints-description constraint-list))
 974
 975 (defun make-constraints-description (constraint-list)
 976   (if constraint-list
 977       (let ((string ""))
 978         (do ((constraint constraint-list (cdr constraint)))
 979             ((null constraint) string)
 980           (let ((output (assoc (symbol-name (car constraint))
 981                                *constraint-types*
 982                                :test #'equal)))
 983             (if (null output)
 984                 (error 'sql-user-error
 985                        :message (format nil "unsupported column constraint '~A'"
 986                                         constraint))
 987                 (setq string (concatenate 'string string (cdr output))))
 988             (if (< 1 (length constraint))
 989                 (setq string (concatenate 'string string " "))))))))
 990