X-Git-Url: http://git.kpe.io/?p=clsql.git;a=blobdiff_plain;f=doc%2Fref-ooddl.xml;h=6ea4d9cdccba6290377c343842c48c5660099217;hp=ebe7de14b369f8d5b4ed360773f9f5b41a717023;hb=e877b742b7e9a3d0ce6d4080bb78aada354ffa88;hpb=39ee7191fd3087c2d7e149b33dd3e985db021721 diff --git a/doc/ref-ooddl.xml b/doc/ref-ooddl.xml index ebe7de1..6ea4d9c 100644 --- a/doc/ref-ooddl.xml +++ b/doc/ref-ooddl.xml @@ -8,10 +8,25 @@ Object Oriented Data Definition Language (OODDL) - + - + The Object Oriented Data Definition Language (OODDL) provides + access to relational SQL tables using Common Lisp Object System + (CLOS) objects. SQL tables are mapped to CLOS objects with the + SQL columns being mapped to slots of the CLOS object. + + The mapping between SQL tables and CLOS objects is defined + with the macro def-view-class. SQL + tables are created with create-view-from-class + and SQL tables can be deleted with drop-view-from-class. + + The above functions refer to the Lisp view of the SQL + table. This Lisp view should not be confused with SQL VIEW statement. + @@ -23,11 +38,11 @@ Class Precedence List - - standard-db-object - standard-object - t - + + standard-db-object + standard-object + t + @@ -41,42 +56,60 @@ Slots - - slot VIEW-DATABASE is of type T - + + slot VIEW-DATABASE is of type (OR NULL DATABASE) + which stores the associated database for the + instance. + - + - *DEFAULT-VARCHAR-LENGTH* - + *DEFAULT-STRING-LENGTH* + Default length of SQL strings. Variable Value Type - + Fixnum Initial Value - nil + 255 - Description - + Description + + If a slot of a class defined by + DEF-VIEW-CLASS is of the type + STRING or VARCHAR and does + not have a length specified, then the value of this variable + is used as SQL length. + Examples - + (let ((*default-string-length* 80)) + (def-view-class s80 () + ((a :type string) + (b :type (string 80)) + (c :type varchar)))) + (create-view-from-class 's80) + + The above code causes a SQL table to be created with the SQL command + + CREATE TABLE (A VARCHAR(80), B CHAR(80), C VARCHAR(80)) Affected By - None. + Some SQL backends do not support VARCHAR + lengths greater than 255 . See Also @@ -84,72 +117,111 @@ Notes - None. + This is a CLSQL extension to the CommonSQL API. CREATE-VIEW-FROM-CLASS - + Create a SQL table from a view class. Function Syntax - (CREATE-VIEW-FROM-CLASS VIEW-CLASS-NAME &KEY (DATABASE *DEFAULT-DATABASE*) (TRANSACTIONS T)) [function] => + (create-view-from-class view-class-name &key (database *default-database*) (transactions t)) => Arguments and Values - + + view-class-name + + + The name of a view class that has been defined with + def-view-class. + + + + + database + + + The database in which to create the SQL table. + + + + + transactions + + + When &nil; specifies that a table type which does not support transactions should be used. + + + Description - Creates a table as defined by the View Class - VIEW-CLASS-NAME in DATABASE which defaults to - *DEFAULT-DATABASE*. + + Creates a table as defined by the View Class + view-class-name in database. Examples - + * (def-view-class 'foo () ((a :type (string 80)))) + #<CLSQL-SYS::STANDARD-DB-CLASS FOO> + * (create-view-from-class 'foo) + * (list-tables) + ("FOO") Side Effects - + Causes a table to be created in the SQL database. Affected by - - - + Most SQL database systems will signal an error if a table + creation is attempted when a table with the same name already + exists. The SQL user, as specified in the database connection, + must have sufficient permission for table creation. Exceptional Situations - + A condition will be signaled if the table can not be created + in the SQL database. See Also - - - + + def-view-class + drop-view-from-class + Notes - + Currently, only &mysql; supports transactionless + tables. &clsql; provides the ability to create such tables for + applications which would benefit from faster table access and + do not require transaction support. + + + The case of the table name is determined by the type of the + database. &mysql;, for example, creates databases in upper-case + while &postgresql; uses lowercase. @@ -157,96 +229,493 @@ DEF-VIEW-CLASS - - Function + Defines CLOS classes with mapping to SQL database. + Macro Syntax - (DEF-VIEW-CLASS CLASS SUPERS SLOTS &REST CL-OPTIONS) [macro] => + (def-view-class name superclasses slots &rest class-options) => class Arguments and Values - + + name + + + The class name. + + + + + name + + + The superclasses for the defined class. + + + + + slots + + + The class slot definitions. + + + + + class + + + The defined class. + + + + + Slot Options + + + + :db-kind - specifies the kind of + database mapping which is performed for this slot and defaults + to :base which indicates that the + slot maps to an ordinary column of the database table. A + :db-kind value of + :key indicates that this slot is + a special kind of :base slot + which maps onto a column which is one of the unique keys + for the database table, the value + :join indicates this slot + represents a join onto another View Class which contains + View Class objects, and the value + :virtual indicates a standard + CLOS slot which does not map onto columns of the + database table. + + + + + :db-info - if a slot is specified with + :db-kind :join, the + slot option :db-info contains a property list + which specifies the nature of the join. The valid members of the list + are: + + + + + :join-class + class-name - the name of the + class to join on. + + + + + :home-key + slot-name - the name of the slot + of this class for joining + + + + + :foreign-key + slot-name - the name of the slot + of the :join-class for joining + + + + + :target-slot + target-slot - this is an optional + parameter. If specified, then the join slot of the + defining class will contain instances of this target + slot rather than of the join class. This can be useful + when the :join-class is an + intermediate class in a + many-to-many relationship and the + application is actually interested in the + :target-slot. + + + + + :retrieval + time - The default value is + :deferred, which defers filling + this slot until the value is accessed. The other valid + value is :immediate which + performs the SQL query when the instance of the class + is created. In this case, the + :set is automatically set to + &nil; + + + + + :set + set - This controls what is stored in the join slot. + The default value is &t;. When set is &t; and + target-slot is undefined, the join slot will contain + a list of instances of the join class. Whereas, if target-slot is defined, + then the join slot will contain a list of pairs of (target-value join-instance). + When set is &nil;, the join slot will contain a single instances. + + + + + + + :type - for slots of + :db-kind :base or + :key, the :type slot + option has a special interpretation such that Lisp + types, such as string, integer and float are + automatically converted into appropriate SQL types for + the column onto which the slot maps. This behaviour may + be overridden using the :db-type slot + option. The valid values are: + + + string - a variable length character field up to + *default-string-length* characters. + + + (string n) - a fixed length character field + n characters long. + + + varchar - a variable length character field up to + *default-string-length* characters. + + + (varchar n) - a variable length character field up to + n characters in length. + + + char - a single character field + + integer - signed integer at least 32-bits wide + (integer n) + float + (float n) + long-float + number + (number n) + (number n p) + + smallint - An integer column 16-bits + wide. [not supported by all database backends] + + + bigint - An integer column + 64-bits wide. [not supported by all database backends] + + + universal-time - an integer + field sufficiently wide to store a + universal-time. On most databases, a slot of this + type assigned a SQL type of + BIGINT + + + wall-time - a slot which + stores a date and time in a SQL timestamp + column. &clsql; provides a number of time + manipulation functions to support objects of type + wall-time. + + + duration - stores a duration structure. + &clsql; provides routines for wall-time and duration + processing. + + boolean - stores a &t; or &nil; value. + + generalized-boolean - similar + to a boolean in that either a + &t; or &nil; value is stored in the SQL + database. However, any Lisp object can be stored in + the Lisp object. A Lisp value of &nil; is stored as + FALSE in the database, any + other Lisp value is stored as + TRUE. + + + keyword - stores a keyword + + symbol - stores a symbol + + list - stores a list by writing it to a string. The items + in the list must be able to be readable written. + + vector - stores a vector similarly to list + array - stores a array similarly to list + + + + + + + :column - specifies the name of + the SQL column which the slot maps onto, if + :db-kind is not + :virtual, and defaults to the + slot name. If the slot name is used for the SQL column + name, any hypens in the slot name are converted + to underscore characters. + + + + + :void-value - specifies + the value to store in the Lisp instance if the SQL value is NULL and defaults + to NIL. + + + + + :db-constraints - is a string + representing an SQL table constraint expression or a + list of such strings. + + + + + :db-type - a string to specify the SQL + column type. If specified, this string overrides the SQL + column type as computed from the :type + slot value. + + + + + + Class Options + + + + + :base-table - specifies the name of the + SQL database table. The default value is the class name. Like slot names, + hypens in the class name are converted to underscore characters. + + + + + Description - Creates a View Class called CLASS whose slots SLOTS can - map onto the attributes of a table in a database. If SUPERS is - nil then the superclass of CLASS will be STANDARD-DB-OBJECT, - otherwise SUPERS is a list of superclasses for CLASS which - must include STANDARD-DB-OBJECT or a descendent of this - class. The syntax of DEFCLASS is extended through the addition - of a class option :base-table which defines the database table - onto which the View Class maps and which defaults to - CLASS. The DEFCLASS syntax is also extended through additional - slot options. The :db-kind slot option specifies the kind of - DB mapping which is performed for this slot and defaults to - :base which indicates that the slot maps to an ordinary column - of the database table. A :db-kind value of :key indicates that - this slot is a special kind of :base slot which maps onto a - column which is one of the unique keys for the database table, - the value :join indicates this slot represents a join onto - another View Class which contains View Class objects, and the - value :virtual indicates a standard CLOS slot which does not - map onto columns of the database table. If a slot is specified - with :db-kind :join, the slot option :db-info contains a list - which specifies the nature of the join. For slots of :db-kind - :base or :key, the :type slot option has a special - interpretation such that Lisp types, such as string, integer - and float are automatically converted into appropriate SQL - types for the column onto which the slot maps. This behaviour - may be over-ridden using the :db-type slot option which is a - string specifying the vendor-specific database type for this - slot's column definition in the database. The :column slot - option specifies the name of the SQL column which the slot - maps onto, if :db-kind is not :virtual, and defaults to the - slot name. The :void-value slot option specifies the value to - store if the SQL value is NULL and defaults to NIL. The - :db-constraints slot option is a string representing an SQL - table constraint expression or a list of such strings. + + Creates a View Class called name whose + slots slots can map onto the attributes + of a table in a database. If + superclasses is &nil; then the + superclass of class will be + standard-db-object, otherwise + superclasses is a list of superclasses + for class which must include + standard-db-object or a descendent of this + class. + Examples + + The following examples are from the &clsql; test suite. + - +(def-view-class person (thing) + ((height :db-kind :base :accessor height :type float + :initarg :height) + (married :db-kind :base :accessor married :type boolean + :initarg :married) + (birthday :type clsql:wall-time :initarg :birthday) + (bd-utime :type clsql:universal-time :initarg :bd-utime) + (hobby :db-kind :virtual :initarg :hobby :initform nil))) + +(def-view-class employee (person) + ((emplid + :db-kind :key + :db-constraints :not-null + :type integer + :initarg :emplid) + (groupid + :db-kind :key + :db-constraints :not-null + :type integer + :initarg :groupid) + (first-name + :accessor first-name + :type (varchar 30) + :initarg :first-name) + (last-name + :accessor last-name + :type (varchar 30) + :initarg :last-name) + (email + :accessor employee-email + :type (varchar 100) + :initarg :email) + (ecompanyid + :type integer + :initarg :companyid) + (company + :accessor employee-company + :db-kind :join + :db-info (:join-class company + :home-key ecompanyid + :foreign-key companyid + :set nil)) + (managerid + :type integer + :initarg :managerid) + (manager + :accessor employee-manager + :db-kind :join + :db-info (:join-class employee + :home-key managerid + :foreign-key emplid + :set nil)) + (addresses + :accessor employee-addresses + :db-kind :join + :db-info (:join-class employee-address + :home-key emplid + :foreign-key aemplid + :target-slot address + :set t))) + (:base-table employee)) + +(def-view-class company () + ((companyid + :db-kind :key + :db-constraints :not-null + :type integer + :initarg :companyid) + (groupid + :db-kind :key + :db-constraints :not-null + :type integer + :initarg :groupid) + (name + :type (varchar 100) + :initarg :name) + (presidentid + :type integer + :initarg :presidentid) + (president + :reader president + :db-kind :join + :db-info (:join-class employee + :home-key presidentid + :foreign-key emplid + :set nil)) + (employees + :reader company-employees + :db-kind :join + :db-info (:join-class employee + :home-key (companyid groupid) + :foreign-key (ecompanyid groupid) + :set t)))) + +(def-view-class address () + ((addressid + :db-kind :key + :db-constraints :not-null + :type integer + :initarg :addressid) + (street-number + :type integer + :initarg :street-number) + (street-name + :type (varchar 30) + :void-value "" + :initarg :street-name) + (city + :column "city_field" + :void-value "no city" + :type (varchar 30) + :initarg :city) + (postal-code + :column zip + :type integer + :void-value 0 + :initarg :postal-code)) + (:base-table addr)) + +;; many employees can reside at many addressess +(def-view-class employee-address () + ((aemplid :type integer :initarg :emplid) + (aaddressid :type integer :initarg :addressid) + (verified :type boolean :initarg :verified) + (address :db-kind :join + :db-info (:join-class address + :home-key aaddressid + :foreign-key addressid + :retrieval :immediate))) + (:base-table "ea_join")) + +(def-view-class deferred-employee-address () + ((aemplid :type integer :initarg :emplid) + (aaddressid :type integer :initarg :addressid) + (verified :type boolean :initarg :verified) + (address :db-kind :join + :db-info (:join-class address + :home-key aaddressid + :foreign-key addressid + :retrieval :deferred + :set nil))) + (:base-table "ea_join")) Side Effects - - - + Creates a new CLOS class. Affected by - - - + Nothing. Exceptional Situations - + None. See Also - - - + + create-view-from-class + standard-db-object + drop-view-from-class + Notes - + The actual SQL type for a column depends up the database type + in which the SQL table is stored. As an example, the view + class type (varchar 100) specifies a + SQL column type VARCHAR(100) in &mysql; + and a column type VARCHAR2(100) in + &oracle; + + + The actual lisp type for a slot may be different than the + value specified by the :type attribute. + For example, a slot declared with ":type (string + 30)" actually sets the slots Lisp type as + (or null string). This is to allow a + &nil; value or a string shorter than 30 characters to be + stored in the slot. @@ -254,65 +723,78 @@ DROP-VIEW-FROM-CLASS - + Delete table from SQL database. Function Syntax - (DROP-VIEW-FROM-CLASS VIEW-CLASS-NAME &KEY (DATABASE *DEFAULT-DATABASE*)) [function] => + (drop-view-from-class view-class-name &key (database *default-database*)) => Arguments and Values - + + view-class-name + + + The name of the view class. + + + Description Removes a table defined by the View Class - VIEW-CLASS-NAME from DATABASE which defaults to - *DEFAULT-DATABASE*. + VIEW-CLASS-NAME from + DATABASE which defaults to + *DEFAULT-DATABASE*. Examples - + * (list-tables) + ("FOO" "BAR") + * (drop-view-from-class 'foo) + * (list-tables) + ("BAR") Side Effects - + Deletes a table from the SQL database. Affected by - - - + Whether the specified table exists in the SQL database. Exceptional Situations - + A condition may be signalled if the table does not exist in + the SQL database or if the SQL connection does not have + sufficient permissions to delete tables. See Also - - - + + create-view-from-class + def-view-class + Notes - + @@ -320,73 +802,104 @@ LIST-CLASSES - + List classes for tables in SQL database. Function Syntax - (LIST-CLASSES &KEY (TEST #'IDENTITY) (ROOT-CLASS (FIND-CLASS 'STANDARD-DB-OBJECT)) (DATABASE *DEFAULT-DATABASE*)) [function] => + (list-classes &key (test #'identity) (root-class (find-class 'standard-db-object)) (database *default-database*)) => classes Arguments and Values - + + test + + + a function used to filter the search. By default, identity is used which + will return all classes. + + + + + root-class + + + specifies the root class to the search. By default, standard-db-object is used + which is the root for all view classes. + + + + + database + + + The database to search for view classes. + + + + + classes + + + List of view classes. + + + Description - Returns a list of all the View Classes which - are connected to DATABASE, which defaults to - *DEFAULT-DATABASE*, and which descend from the class - ROOT-CLASS and which satisfy the function TEST. By - default ROOT-CLASS is STANDARD-DB-OBJECT and TEST is - IDENTITY. + Returns a list of all the View Classes which have been + defined in the Lisp session and are connected to + database and which descended from the + class root-class and which satisfy the + function test. Examples - + * (list-classes) + (#<clsql-sys::standard-db-class big> #<clsql-sys::standard-db-class employee-address> + #<clsql-sys::standard-db-class address> #<clsql-sys::standard-db-class company> + #<clsql-sys::standard-db-class employee>) + + * (list-classes :test #'(lambda (c) (> (length (symbol-name (class-name c))) 3))) + (#<clsql-sys::standard-db-class employee-address> #<clsql-sys::standard-db-class address> + #<clsql-sys::standard-db-class company> #<clsql-sys::standard-db-class employee>) Side Effects - + None. Affected by - - - + + Which view classes have been defined in the Lisp session. + Exceptional Situations - + None. See Also - - - - - - - Notes - - + + def-view-class + - -